Headline
CVE-2022-23635: ISTIO-SECURITY-2022-003
Istio is an open platform to connect, manage, and secure microservices. In affected versions the Istio control plane, istiod, is vulnerable to a request processing error, allowing a malicious attacker that sends a specially crafted message which results in the control plane crashing. This endpoint is served over TLS port 15012, but does not require any authentication from the attacker. For simple installations, Istiod is typically only reachable from within the cluster, limiting the blast radius. However, for some deployments, especially multicluster topologies, this port is exposed over the public internet. There are no effective workarounds, beyond upgrading. Limiting network access to Istiod to the minimal set of clients can help lessen the scope of the vulnerability to some extent.
Multiple CVEs related to istiod Denial of Service and Envoy.
Disclosure Details
CVE(s)
CVE-2022-23635
CVE-2021-43824
CVE-2021-43825
CVE-2021-43826
CVE-2022-21654
CVE-2022-21655
CVE-2022-23606
CVSS Impact Score
7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Affected Releases
All releases prior to 1.11.0
1.11.0 to 1.11.6
1.12.0 to 1.12.3
1.13.0
CVE****CVE-2022-23635
- CVE-2022-23635: (CVSS Score 7.5, High): Unauthenticated control plane denial of service attack.
The Istio control plane, istiod, is vulnerable to a request processing error, allowing a malicious attacker that sends a specially crafted message which results in the control plane crashing. This endpoint is served over TLS port 15012, but does not require any authentication from the attacker.
For simple installations, istiod is typically only reachable from within the cluster, limiting the blast radius. However, for some deployments, especially multicluster topologies, this port is exposed over the public internet.
Envoy CVEs
At this time it is not believed that Istio is vulnerable to these CVEs in Envoy. They are listed, however, to be transparent.
CVE ID
Score, Rating
Description
Fixed in 1.13.1
Fixed in 1.12.4
Fixed in 1.11.7
CVE-2021-43824
6.5, Medium
Potential null pointer dereference when using JWT filter safe_regex match.
Yes
Yes
Yes
CVE-2021-43825
6.1, Medium
Use-after-free when response filters increase response data, and increased data exceeds downstream buffer limits.
Yes
Yes
Yes
CVE-2021-43826
6.1, Medium
Use-after-free when tunneling TCP over HTTP, if downstream disconnects during upstream connection establishment.
Yes
Yes
Yes
CVE-2022-21654
7.3, High
Incorrect configuration handling allows mTLS session re-use without re-validation after validation settings have changed.
Yes
Yes
Yes
CVE-2022-21655
7.5, High
Incorrect handling of internal redirects to routes with a direct response entry.
Yes
Yes
Yes
CVE-2022-23606
4.4, Moderate
Stack exhaustion when a cluster is deleted via Cluster Discovery Service.
Yes
Yes
N/A
CVE-2022-21656
3.1, Low
X.509 subjectAltName matching (and nameConstraints) bypass.
No, next release.
No, next release.
Envoy did not backport this fix.
CVE-2022-21657
3.1, Low
X.509 Extended Key Usage and Trust Purposes bypass
No, next release.
No, next release.
No, next release.
Am I Impacted?
You are at most risk if you are running Istio in a multi-cluster environment, or if you have exposed your istiod externally.
Credit
We would like to thank Adam Korczynski (ADA Logics) and John Howard (Google) for the report and the fix.
ISTIO-SECURITY-2022-004
ISTIO-SECURITY-2022-001
Related news
gRPC contains a vulnerability that allows hpack table accounting errors could lead to unwanted disconnects between clients and servers in exceptional cases/ Three vectors were found that allow the following DOS attacks: - Unbounded memory buffering in the HPACK parser - Unbounded CPU consumption in the HPACK parser The unbounded CPU consumption is down to a copy that occurred per-input-block in the parser, and because that could be unbounded due to the memory copy bug we end up with an O(n^2) parsing loop, with n selected by the client. The unbounded memory buffering bugs: - The header size limit check was behind the string reading code, so we needed to first buffer up to a 4 gigabyte string before rejecting it as longer than 8 or 16kb. - HPACK varints have an encoding quirk whereby an infinite number of 0’s can be added at the start of an integer. gRPC’s hpack parser needed to read all of them before concluding a parse. - gRPC’s metadata overflow check was performed per frame, so ...
A parsing vulnerability for the MessageSet type in the ProtocolBuffers versions prior to and including 3.16.1, 3.17.3, 3.18.2, 3.19.4, 3.20.1 and 3.21.5 for protobuf-cpp, and versions prior to and including 3.16.1, 3.17.3, 3.18.2, 3.19.4, 3.20.1 and 4.21.5 for protobuf-python can lead to out of memory failures. A specially crafted message with multiple key-value per elements creates parsing issues, and can lead to a Denial of Service against services receiving unsanitized input. We recommend upgrading to versions 3.18.3, 3.19.5, 3.20.2, 3.21.6 for protobuf-cpp and 3.18.3, 3.19.5, 3.20.2, 4.21.6 for protobuf-python. Versions for 3.16 and 3.17 are no longer updated.
A parsing vulnerability for the MessageSet type in the ProtocolBuffers versions prior to and including 3.16.1, 3.17.3, 3.18.2, 3.19.4, 3.20.1 and 3.21.5 for protobuf-cpp, and versions prior to and including 3.16.1, 3.17.3, 3.18.2, 3.19.4, 3.20.1 and 4.21.5 for protobuf-python can lead to out of memory failures. A specially crafted message with multiple key-value per elements creates parsing issues, and can lead to a Denial of Service against services receiving unsanitized input. We recommend upgrading to versions 3.18.3, 3.19.5, 3.20.2, 3.21.6 for protobuf-cpp and 3.18.3, 3.19.5, 3.20.2, 4.21.6 for protobuf-python. Versions for 3.16 and 3.17 are no longer updated.
A parsing vulnerability for the MessageSet type in the ProtocolBuffers versions prior to and including 3.16.1, 3.17.3, 3.18.2, 3.19.4, 3.20.1 and 3.21.5 for protobuf-cpp, and versions prior to and including 3.16.1, 3.17.3, 3.18.2, 3.19.4, 3.20.1 and 4.21.5 for protobuf-python can lead to out of memory failures. A specially crafted message with multiple key-value per elements creates parsing issues, and can lead to a Denial of Service against services receiving unsanitized input. We recommend upgrading to versions 3.18.3, 3.19.5, 3.20.2, 3.21.6 for protobuf-cpp and 3.18.3, 3.19.5, 3.20.2, 4.21.6 for protobuf-python. Versions for 3.16 and 3.17 are no longer updated.
A parsing vulnerability for the MessageSet type in the ProtocolBuffers versions prior to and including 3.16.1, 3.17.3, 3.18.2, 3.19.4, 3.20.1 and 3.21.5 for protobuf-cpp, and versions prior to and including 3.16.1, 3.17.3, 3.18.2, 3.19.4, 3.20.1 and 4.21.5 for protobuf-python can lead to out of memory failures. A specially crafted message with multiple key-value per elements creates parsing issues, and can lead to a Denial of Service against services receiving unsanitized input. We recommend upgrading to versions 3.18.3, 3.19.5, 3.20.2, 3.21.6 for protobuf-cpp and 3.18.3, 3.19.5, 3.20.2, 4.21.6 for protobuf-python. Versions for 3.16 and 3.17 are no longer updated.
A parsing vulnerability for the MessageSet type in the ProtocolBuffers versions prior to and including 3.16.1, 3.17.3, 3.18.2, 3.19.4, 3.20.1 and 3.21.5 for protobuf-cpp, and versions prior to and including 3.16.1, 3.17.3, 3.18.2, 3.19.4, 3.20.1 and 4.21.5 for protobuf-python can lead to out of memory failures. A specially crafted message with multiple key-value per elements creates parsing issues, and can lead to a Denial of Service against services receiving unsanitized input. We recommend upgrading to versions 3.18.3, 3.19.5, 3.20.2, 3.21.6 for protobuf-cpp and 3.18.3, 3.19.5, 3.20.2, 4.21.6 for protobuf-python. Versions for 3.16 and 3.17 are no longer updated.
A parsing vulnerability for the MessageSet type in the ProtocolBuffers versions prior to and including 3.16.1, 3.17.3, 3.18.2, 3.19.4, 3.20.1 and 3.21.5 for protobuf-cpp, and versions prior to and including 3.16.1, 3.17.3, 3.18.2, 3.19.4, 3.20.1 and 4.21.5 for protobuf-python can lead to out of memory failures. A specially crafted message with multiple key-value per elements creates parsing issues, and can lead to a Denial of Service against services receiving unsanitized input. We recommend upgrading to versions 3.18.3, 3.19.5, 3.20.2, 3.21.6 for protobuf-cpp and 3.18.3, 3.19.5, 3.20.2, 4.21.6 for protobuf-python. Versions for 3.16 and 3.17 are no longer updated.
A parsing vulnerability for the MessageSet type in the ProtocolBuffers versions prior to and including 3.16.1, 3.17.3, 3.18.2, 3.19.4, 3.20.1 and 3.21.5 for protobuf-cpp, and versions prior to and including 3.16.1, 3.17.3, 3.18.2, 3.19.4, 3.20.1 and 4.21.5 for protobuf-python can lead to out of memory failures. A specially crafted message with multiple key-value per elements creates parsing issues, and can lead to a Denial of Service against services receiving unsanitized input. We recommend upgrading to versions 3.18.3, 3.19.5, 3.20.2, 3.21.6 for protobuf-cpp and 3.18.3, 3.19.5, 3.20.2, 4.21.6 for protobuf-python. Versions for 3.16 and 3.17 are no longer updated.
A parsing vulnerability for the MessageSet type in the ProtocolBuffers versions prior to and including 3.16.1, 3.17.3, 3.18.2, 3.19.4, 3.20.1 and 3.21.5 for protobuf-cpp, and versions prior to and including 3.16.1, 3.17.3, 3.18.2, 3.19.4, 3.20.1 and 4.21.5 for protobuf-python can lead to out of memory failures. A specially crafted message with multiple key-value per elements creates parsing issues, and can lead to a Denial of Service against services receiving unsanitized input. We recommend upgrading to versions 3.18.3, 3.19.5, 3.20.2, 3.21.6 for protobuf-cpp and 3.18.3, 3.19.5, 3.20.2, 4.21.6 for protobuf-python. Versions for 3.16 and 3.17 are no longer updated.
A parsing vulnerability for the MessageSet type in the ProtocolBuffers versions prior to and including 3.16.1, 3.17.3, 3.18.2, 3.19.4, 3.20.1 and 3.21.5 for protobuf-cpp, and versions prior to and including 3.16.1, 3.17.3, 3.18.2, 3.19.4, 3.20.1 and 4.21.5 for protobuf-python can lead to out of memory failures. A specially crafted message with multiple key-value per elements creates parsing issues, and can lead to a Denial of Service against services receiving unsanitized input. We recommend upgrading to versions 3.18.3, 3.19.5, 3.20.2, 3.21.6 for protobuf-cpp and 3.18.3, 3.19.5, 3.20.2, 4.21.6 for protobuf-python. Versions for 3.16 and 3.17 are no longer updated.