{"id":"GHSA-rp9h-rf7g-hwgr","summary":"s2n-tls has undefined behavior at process exit","details":"### Impact\ns2n-tls uses the Linux atexit function to register functions that clean up the global state when the process exits. In multi-threaded environments, the atexit handler may clean up state which is still in use by other threads. When this occurs, the exiting process may experience a segmentation fault or other undefined behavior. \n\nCustomers of AWS services do not need to take action. Applications using s2n-tls should upgrade to the most recent release of s2n-tls.\n\n**Impacted versions**: \u003c v1.5.9.\n\n### Patches\nThe patch commit [493b771](https://github.com/aws/s2n-tls/commit/493b77167dc367c394de23cfe78a029298e2a254) is included in s2n-tls v1.5.9 [1]\n\n### Workarounds\nThe atexit handler may be disabled by calling `s2n_disable_atexit()` prior to initializing s2n-tls. The atexit handler is off by default in the patched versions. For further details, refer to [s2n-tls Usage Guide: Initialization and Teardown](https://github.com/aws/s2n-tls/blob/main/docs/usage-guide/topics/ch02-initialization.md).\n\nIf you have any questions or comments about this advisory, we ask that you contact AWS/Amazon Security via our vulnerability reporting page [2] or directly via email to [aws-security@amazon.com](mailto:aws-security@amazon.com). Please do not create a public GitHub issue.\n\n[1] https://github.com/aws/s2n-tls/releases/tag/v1.5.9\n[2] Vulnerability reporting page: https://aws.amazon.com/security/vulnerability-reporting\n","modified":"2026-09-10T03:50:56.039654227Z","published":"2024-11-14T15:45:55Z","database_specific":{"github_reviewed_at":"2024-11-14T15:45:55Z","nvd_published_at":null,"cwe_ids":[],"severity":"LOW","github_reviewed":true},"references":[{"type":"WEB","url":"https://github.com/aws/s2n-tls/security/advisories/GHSA-rp9h-rf7g-hwgr"},{"type":"WEB","url":"https://github.com/aws/s2n-tls/commit/493b77167dc367c394de23cfe78a029298e2a254"},{"type":"PACKAGE","url":"https://github.com/aws/s2n-tls"},{"type":"WEB","url":"https://github.com/aws/s2n-tls/releases/tag/v1.5.9"}],"affected":[{"package":{"name":"s2n-tls","ecosystem":"crates.io","purl":"pkg:cargo/s2n-tls"},"ranges":[{"type":"SEMVER","events":[{"introduced":"0"},{"fixed":"0.3.7"}]}],"database_specific":{"source":"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2024/11/GHSA-rp9h-rf7g-hwgr/GHSA-rp9h-rf7g-hwgr.json"}}],"schema_version":"1.9.0"}