Red Hat Security Advisory 2023-4033-01

Red Hat Security Advisory 2023-7543-01 - An update for c-ares is now available for Red Hat Enterprise Linux 8.8 Extended Update Support. Issues addressed include a buffer overflow vulnerability.

Red Hat Security Advisory 2023-7207-01 - An update for c-ares is now available for Red Hat Enterprise Linux 8. Issues addressed include a buffer over-read vulnerability.

Gentoo Linux Security Advisory 202310-9 - Multiple vulnerabilities have been discovered in c-ares the worst of which could result in Denial of Service. Versions greater than or equal to 1.19.1 are affected.

Ubuntu Security Notice 6164-2 - USN-6164-1 fixed several vulnerabilities in c-ares. This update provides the corresponding update for Ubuntu 16.04 LTS and Ubuntu 18.04 LTS. Hannes Moesl discovered that c-ares incorrectly handled certain ipv6 addresses. An attacker could use this issue to cause c-ares to crash, resulting in a denial of service, or possibly execute arbitrary code.

Red Hat OpenShift Container Platform release 4.13.6 is now available with updates to packages and images that fix several bugs and add enhancements. This release includes a security update for Red Hat OpenShift Container Platform 4.13. Red Hat Product Security has rated this update as having a security impact of [impact]. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section.This content is licensed under the Creative Commons Attribution 4.0 International License (https://creativecommons.org/licenses/by/4.0/). If you distribute this content, or a modified version of it, you must provide attribution to Red Hat Inc. and provide a link to the original. Related CVEs: * CVE-2022-41723: A flaw was found in golang. A maliciously crafted HTTP/2 stream could cause excessive CPU consumption in the HPACK decoder, sufficient to cause a denial of service from a small number...

Red Hat Security Advisory 2023-4091-01 - Red Hat OpenShift Container Platform is Red Hat's cloud computing Kubernetes application platform solution designed for on-premise or private cloud deployments. This advisory contains the container images for Red Hat OpenShift Container Platform 4.13.5. Issues addressed include a denial of service vulnerability.

Red Hat OpenShift Container Platform release 4.13.5 is now available with updates to packages and images that fix several bugs and add enhancements. This release includes a security update for Red Hat OpenShift Container Platform 4.13. Red Hat Product Security has rated this update as having a security impact of Moderate. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section.This content is licensed under the Creative Commons Attribution 4.0 International License (https://creativecommons.org/licenses/by/4.0/). If you distribute this content, or a modified version of it, you must provide attribution to Red Hat Inc. and provide a link to the original. Related CVEs: * CVE-2022-41717: A flaw was found in the net/http library of the golang package. This flaw allows an attacker to cause excessive memory growth in a Go server accepting HTTP/2 requests. HTTP/2 server c...

Red Hat Security Advisory 2023-4039-01 - Node.js is a software development platform for building fast and scalable network applications in the JavaScript programming language. Issues addressed include a denial of service vulnerability.

Red Hat Security Advisory 2023-4039-01 - Node.js is a software development platform for building fast and scalable network applications in the JavaScript programming language. Issues addressed include a denial of service vulnerability.

Red Hat Security Advisory 2023-4039-01 - Node.js is a software development platform for building fast and scalable network applications in the JavaScript programming language. Issues addressed include a denial of service vulnerability.

Red Hat Security Advisory 2023-4034-01 - Node.js is a software development platform for building fast and scalable network applications in the JavaScript programming language. Issues addressed include a denial of service vulnerability.

Red Hat Security Advisory 2023-4034-01 - Node.js is a software development platform for building fast and scalable network applications in the JavaScript programming language. Issues addressed include a denial of service vulnerability.

Red Hat Security Advisory 2023-4034-01 - Node.js is a software development platform for building fast and scalable network applications in the JavaScript programming language. Issues addressed include a denial of service vulnerability.

Red Hat Security Advisory 2023-4036-01 - Node.js is a software development platform for building fast and scalable network applications in the JavaScript programming language. Issues addressed include a denial of service vulnerability.

Red Hat Security Advisory 2023-4035-01 - Node.js is a software development platform for building fast and scalable network applications in the JavaScript programming language. Issues addressed include buffer overflow and denial of service vulnerabilities.

An update for the nodejs:16 module is now available for Red Hat Enterprise Linux 8. Red Hat Product Security has rated this update as having a security impact of Important. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section.This content is licensed under the Creative Commons Attribution 4.0 International License (https://creativecommons.org/licenses/by/4.0/). If you distribute this content, or a modified version of it, you must provide attribution to Red Hat Inc. and provide a link to the original. Related CVEs: * CVE-2023-31124: A flaw was found in c-ares. This issue occurs when cross-compiling c-ares and using the autotools build system, CARES_RANDOM_FILE will not be set, as seen when cross-compiling aarch64 android. As a result, it will downgrade to rand(), which could allow an attacker to utilize the lack of entropy by not using a CSPRNG. * CVE-2023-3113...

An update for the nodejs:18 module is now available for Red Hat Enterprise Linux 8. Red Hat Product Security has rated this update as having a security impact of Important. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section.This content is licensed under the Creative Commons Attribution 4.0 International License (https://creativecommons.org/licenses/by/4.0/). If you distribute this content, or a modified version of it, you must provide attribution to Red Hat Inc. and provide a link to the original. Related CVEs: * CVE-2022-4904: A flaw was found in the c-ares package. The ares_set_sortlist is missing checks about the validity of the input string, which allows a possible arbitrary length stack overflow. This issue may cause a denial of service or a limited impact on confidentiality and integrity. * CVE-2023-31124: A flaw was found in c-ares. This issue occurs...

An update for the nodejs:16 module is now available for Red Hat Enterprise Linux 8. Red Hat Product Security has rated this update as having a security impact of Important. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section.This content is licensed under the Creative Commons Attribution 4.0 International License (https://creativecommons.org/licenses/by/4.0/). If you distribute this content, or a modified version of it, you must provide attribution to Red Hat Inc. and provide a link to the original. Related CVEs: * CVE-2023-31124: A flaw was found in c-ares. This issue occurs when cross-compiling c-ares and using the autotools build system, CARES_RANDOM_FILE will not be set, as seen when cross-compiling aarch64 android. As a result, it will downgrade to rand(), which could allow an attacker to utilize the lack of entropy by not using a CSPRNG. * CVE-2023-3113...

An update for the nodejs:18 module is now available for Red Hat Enterprise Linux 8. Red Hat Product Security has rated this update as having a security impact of Important. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section.This content is licensed under the Creative Commons Attribution 4.0 International License (https://creativecommons.org/licenses/by/4.0/). If you distribute this content, or a modified version of it, you must provide attribution to Red Hat Inc. and provide a link to the original. Related CVEs: * CVE-2022-4904: A flaw was found in the c-ares package. The ares_set_sortlist is missing checks about the validity of the input string, which allows a possible arbitrary length stack overflow. This issue may cause a denial of service or a limited impact on confidentiality and integrity. * CVE-2023-31124: A flaw was found in c-ares. This issue occurs...

An update for the nodejs:18 module is now available for Red Hat Enterprise Linux 8. Red Hat Product Security has rated this update as having a security impact of Important. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section.This content is licensed under the Creative Commons Attribution 4.0 International License (https://creativecommons.org/licenses/by/4.0/). If you distribute this content, or a modified version of it, you must provide attribution to Red Hat Inc. and provide a link to the original. Related CVEs: * CVE-2022-4904: A flaw was found in the c-ares package. The ares_set_sortlist is missing checks about the validity of the input string, which allows a possible arbitrary length stack overflow. This issue may cause a denial of service or a limited impact on confidentiality and integrity. * CVE-2023-31124: A flaw was found in c-ares. This issue occurs...

An update for the nodejs:16 module is now available for Red Hat Enterprise Linux 8. Red Hat Product Security has rated this update as having a security impact of Important. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section.This content is licensed under the Creative Commons Attribution 4.0 International License (https://creativecommons.org/licenses/by/4.0/). If you distribute this content, or a modified version of it, you must provide attribution to Red Hat Inc. and provide a link to the original. Related CVEs: * CVE-2023-31124: A flaw was found in c-ares. This issue occurs when cross-compiling c-ares and using the autotools build system, CARES_RANDOM_FILE will not be set, as seen when cross-compiling aarch64 android. As a result, it will downgrade to rand(), which could allow an attacker to utilize the lack of entropy by not using a CSPRNG. * CVE-2023-3113...

An update for the nodejs:16 module is now available for Red Hat Enterprise Linux 8.6 Extended Update Support. Red Hat Product Security has rated this update as having a security impact of Important. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section.This content is licensed under the Creative Commons Attribution 4.0 International License (https://creativecommons.org/licenses/by/4.0/). If you distribute this content, or a modified version of it, you must provide attribution to Red Hat Inc. and provide a link to the original. Related CVEs: * CVE-2023-31124: A flaw was found in c-ares. This issue occurs when cross-compiling c-ares and using the autotools build system, CARES_RANDOM_FILE will not be set, as seen when cross-compiling aarch64 android. As a result, it will downgrade to rand(), which could allow an attacker to utilize the lack of entropy by not using...

An update for the nodejs:16 module is now available for Red Hat Enterprise Linux 8.6 Extended Update Support. Red Hat Product Security has rated this update as having a security impact of Important. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section.This content is licensed under the Creative Commons Attribution 4.0 International License (https://creativecommons.org/licenses/by/4.0/). If you distribute this content, or a modified version of it, you must provide attribution to Red Hat Inc. and provide a link to the original. Related CVEs: * CVE-2023-31124: A flaw was found in c-ares. This issue occurs when cross-compiling c-ares and using the autotools build system, CARES_RANDOM_FILE will not be set, as seen when cross-compiling aarch64 android. As a result, it will downgrade to rand(), which could allow an attacker to utilize the lack of entropy by not using...

An update for the nodejs:16 module is now available for Red Hat Enterprise Linux 8.6 Extended Update Support. Red Hat Product Security has rated this update as having a security impact of Important. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section.This content is licensed under the Creative Commons Attribution 4.0 International License (https://creativecommons.org/licenses/by/4.0/). If you distribute this content, or a modified version of it, you must provide attribution to Red Hat Inc. and provide a link to the original. Related CVEs: * CVE-2023-31124: A flaw was found in c-ares. This issue occurs when cross-compiling c-ares and using the autotools build system, CARES_RANDOM_FILE will not be set, as seen when cross-compiling aarch64 android. As a result, it will downgrade to rand(), which could allow an attacker to utilize the lack of entropy by not using...

An update for rh-nodejs14-nodejs is now available for Red Hat Software Collections. Red Hat Product Security has rated this update as having a security impact of Important. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section.This content is licensed under the Creative Commons Attribution 4.0 International License (https://creativecommons.org/licenses/by/4.0/). If you distribute this content, or a modified version of it, you must provide attribution to Red Hat Inc. and provide a link to the original. Related CVEs: * CVE-2023-31124: A flaw was found in c-ares. This issue occurs when cross-compiling c-ares and using the autotools build system, CARES_RANDOM_FILE will not be set, as seen when cross-compiling aarch64 android. As a result, it will downgrade to rand(), which could allow an attacker to utilize the lack of entropy by not using a CSPRNG. * CVE-2023-3113...

An update for rh-nodejs14-nodejs is now available for Red Hat Software Collections. Red Hat Product Security has rated this update as having a security impact of Important. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section.This content is licensed under the Creative Commons Attribution 4.0 International License (https://creativecommons.org/licenses/by/4.0/). If you distribute this content, or a modified version of it, you must provide attribution to Red Hat Inc. and provide a link to the original. Related CVEs: * CVE-2023-31124: A flaw was found in c-ares. This issue occurs when cross-compiling c-ares and using the autotools build system, CARES_RANDOM_FILE will not be set, as seen when cross-compiling aarch64 android. As a result, it will downgrade to rand(), which could allow an attacker to utilize the lack of entropy by not using a CSPRNG. * CVE-2023-3113...

An update for rh-nodejs14-nodejs is now available for Red Hat Software Collections. Red Hat Product Security has rated this update as having a security impact of Important. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section.This content is licensed under the Creative Commons Attribution 4.0 International License (https://creativecommons.org/licenses/by/4.0/). If you distribute this content, or a modified version of it, you must provide attribution to Red Hat Inc. and provide a link to the original. Related CVEs: * CVE-2023-31124: A flaw was found in c-ares. This issue occurs when cross-compiling c-ares and using the autotools build system, CARES_RANDOM_FILE will not be set, as seen when cross-compiling aarch64 android. As a result, it will downgrade to rand(), which could allow an attacker to utilize the lack of entropy by not using a CSPRNG. * CVE-2023-3113...

An update for nodejs is now available for Red Hat Enterprise Linux 9.0 Extended Update Support. Red Hat Product Security has rated this update as having a security impact of Important. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section.This content is licensed under the Creative Commons Attribution 4.0 International License (https://creativecommons.org/licenses/by/4.0/). If you distribute this content, or a modified version of it, you must provide attribution to Red Hat Inc. and provide a link to the original. Related CVEs: * CVE-2023-31124: A flaw was found in c-ares. This issue occurs when cross-compiling c-ares and using the autotools build system, CARES_RANDOM_FILE will not be set, as seen when cross-compiling aarch64 android. As a result, it will downgrade to rand(), which could allow an attacker to utilize the lack of entropy by not using a CSPRNG. * C...

An update for nodejs is now available for Red Hat Enterprise Linux 9.0 Extended Update Support. Red Hat Product Security has rated this update as having a security impact of Important. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section.This content is licensed under the Creative Commons Attribution 4.0 International License (https://creativecommons.org/licenses/by/4.0/). If you distribute this content, or a modified version of it, you must provide attribution to Red Hat Inc. and provide a link to the original. Related CVEs: * CVE-2023-31124: A flaw was found in c-ares. This issue occurs when cross-compiling c-ares and using the autotools build system, CARES_RANDOM_FILE will not be set, as seen when cross-compiling aarch64 android. As a result, it will downgrade to rand(), which could allow an attacker to utilize the lack of entropy by not using a CSPRNG. * C...

An update for nodejs is now available for Red Hat Enterprise Linux 9.0 Extended Update Support. Red Hat Product Security has rated this update as having a security impact of Important. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section.This content is licensed under the Creative Commons Attribution 4.0 International License (https://creativecommons.org/licenses/by/4.0/). If you distribute this content, or a modified version of it, you must provide attribution to Red Hat Inc. and provide a link to the original. Related CVEs: * CVE-2023-31124: A flaw was found in c-ares. This issue occurs when cross-compiling c-ares and using the autotools build system, CARES_RANDOM_FILE will not be set, as seen when cross-compiling aarch64 android. As a result, it will downgrade to rand(), which could allow an attacker to utilize the lack of entropy by not using a CSPRNG. * C...

Red Hat OpenShift Container Platform release 4.12.23 is now available with updates to packages and images that fix several bugs and add enhancements. This release includes a security update for Red Hat OpenShift Container Platform 4.12. Red Hat Product Security has rated this update as having a security impact of Moderate. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section.This content is licensed under the Creative Commons Attribution 4.0 International License (https://creativecommons.org/licenses/by/4.0/). If you distribute this content, or a modified version of it, you must provide attribution to Red Hat Inc. and provide a link to the original. Related CVEs: * CVE-2023-3089: A compliance problem was found in the Red Hat OpenShift Container Platform. Red Hat discovered that, when FIPS mode was enabled, not all of the cryptographic modules in use were FIPS-...

Red Hat Security Advisory 2023-3915-01 - Red Hat OpenShift Container Platform is Red Hat's cloud computing Kubernetes application platform solution designed for on-premise or private cloud deployments. This advisory contains the container images for Red Hat OpenShift Container Platform 4.11.44.

Red Hat Security Advisory 2023-3741-01 - The c-ares C library defines asynchronous DNS requests and provides name resolving API. Issues addressed include a denial of service vulnerability.

An update for c-ares is now available for Red Hat Enterprise Linux 7. Red Hat Product Security has rated this update as having a security impact of Important. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section.This content is licensed under the Creative Commons Attribution 4.0 International License (https://creativecommons.org/licenses/by/4.0/). If you distribute this content, or a modified version of it, you must provide attribution to Red Hat Inc. and provide a link to the original. Related CVEs: * CVE-2023-32067: A vulnerability was found in c-ares. This issue occurs due to a 0-byte UDP payload that can cause a Denial of Service.

An update for c-ares is now available for Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support, Red Hat Enterprise Linux 8.4 Telecommunications Update Service, and Red Hat Enterprise Linux 8.4 Update Services for SAP Solutions. Red Hat Product Security has rated this update as having a security impact of Important. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section.This content is licensed under the Creative Commons Attribution 4.0 International License (https://creativecommons.org/licenses/by/4.0/). If you distribute this content, or a modified version of it, you must provide attribution to Red Hat Inc. and provide a link to the original. Related CVEs: * CVE-2023-32067: A vulnerability was found in c-ares. This issue occurs due to a 0-byte UDP payload that can cause a Denial of Service.

Red Hat Security Advisory 2023-3662-01 - The c-ares C library defines asynchronous DNS requests and provides name resolving API. Issues addressed include a denial of service vulnerability.

An update for c-ares is now available for Red Hat Enterprise Linux 8.1 Update Services for SAP Solutions. Red Hat Product Security has rated this update as having a security impact of Important. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section.This content is licensed under the Creative Commons Attribution 4.0 International License (https://creativecommons.org/licenses/by/4.0/). If you distribute this content, or a modified version of it, you must provide attribution to Red Hat Inc. and provide a link to the original. Related CVEs: * CVE-2023-32067: c-ares is an asynchronous resolver library. c-ares is vulnerable to denial of service. If a target resolver sends a query, the attacker forges a malformed UDP packet with a length of 0 and returns them to the target resolver. The target resolver erroneously interprets the 0 length as a graceful shutdown of the ...

An update for c-ares is now available for Red Hat Enterprise Linux 8.2 Advanced Update Support, Red Hat Enterprise Linux 8.2 Telecommunications Update Service, and Red Hat Enterprise Linux 8.2 Update Services for SAP Solutions. Red Hat Product Security has rated this update as having a security impact of Important. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section.This content is licensed under the Creative Commons Attribution 4.0 International License (https://creativecommons.org/licenses/by/4.0/). If you distribute this content, or a modified version of it, you must provide attribution to Red Hat Inc. and provide a link to the original. Related CVEs: * CVE-2023-32067: c-ares is an asynchronous resolver library. c-ares is vulnerable to denial of service. If a target resolver sends a query, the attacker forges a malformed UDP packet with a length of 0 and r...

An update for c-ares is now available for Red Hat Enterprise Linux 9.0 Extended Update Support. Red Hat Product Security has rated this update as having a security impact of Important. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section.This content is licensed under the Creative Commons Attribution 4.0 International License (https://creativecommons.org/licenses/by/4.0/). If you distribute this content, or a modified version of it, you must provide attribution to Red Hat Inc. and provide a link to the original. Related CVEs: * CVE-2023-32067: c-ares is an asynchronous resolver library. c-ares is vulnerable to denial of service. If a target resolver sends a query, the attacker forges a malformed UDP packet with a length of 0 and returns them to the target resolver. The target resolver erroneously interprets the 0 length as a graceful shutdown of the connection...

An update for c-ares is now available for Red Hat Enterprise Linux 9. Red Hat Product Security has rated this update as having a security impact of Important. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section.This content is licensed under the Creative Commons Attribution 4.0 International License (https://creativecommons.org/licenses/by/4.0/). If you distribute this content, or a modified version of it, you must provide attribution to Red Hat Inc. and provide a link to the original. Related CVEs: * CVE-2023-32067: c-ares is an asynchronous resolver library. c-ares is vulnerable to denial of service. If a target resolver sends a query, the attacker forges a malformed UDP packet with a length of 0 and returns them to the target resolver. The target resolver erroneously interprets the 0 length as a graceful shutdown of the connection. This issue has been patc...

Debian Linux Security Advisory 5419-1 - Two vulnerabilities were discovered in c-ares, an asynchronous name resolver library.

c-ares is an asynchronous resolver library. ares_inet_net_pton() is vulnerable to a buffer underflow for certain ipv6 addresses, in particular "0::00:00:00/2" was found to cause an issue. C-ares only uses this function internally for configuration purposes which would require an administrator to configure such an address via ares_set_sortlist(). However, users may externally use ares_inet_net_pton() for other purposes and thus be vulnerable to more severe issues. This issue has been fixed in 1.19.1.

c-ares is an asynchronous resolver library. ares_inet_net_pton() is vulnerable to a buffer underflow for certain ipv6 addresses, in particular "0::00:00:00/2" was found to cause an issue. C-ares only uses this function internally for configuration purposes which would require an administrator to configure such an address via ares_set_sortlist(). However, users may externally use ares_inet_net_pton() for other purposes and thus be vulnerable to more severe issues. This issue has been fixed in 1.19.1.

c-ares is an asynchronous resolver library. ares_inet_net_pton() is vulnerable to a buffer underflow for certain ipv6 addresses, in particular "0::00:00:00/2" was found to cause an issue. C-ares only uses this function internally for configuration purposes which would require an administrator to configure such an address via ares_set_sortlist(). However, users may externally use ares_inet_net_pton() for other purposes and thus be vulnerable to more severe issues. This issue has been fixed in 1.19.1.

c-ares is an asynchronous resolver library. When cross-compiling c-ares and using the autotools build system, CARES_RANDOM_FILE will not be set, as seen when cross compiling aarch64 android. This will downgrade to using rand() as a fallback which could allow an attacker to take advantage of the lack of entropy by not using a CSPRNG. This issue was patched in version 1.19.1.

c-ares is an asynchronous resolver library. When /dev/urandom or RtlGenRandom() are unavailable, c-ares uses rand() to generate random numbers used for DNS query ids. This is not a CSPRNG, and it is also not seeded by srand() so will generate predictable output. Input from the random number generator is fed into a non-compilant RC4 implementation and may not be as strong as the original RC4 implementation. No attempt is made to look for modern OS-provided CSPRNGs like arc4random() that is widely available. This issue has been fixed in version 1.19.1.