GHSA-rp9h-rf7g-hwgr
s2n-tls has undefined behavior at process exit
Impact
s2n-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.
Customers of AWS services do not need to take action. Applications using s2n-tls should upgrade to the most recent release of s2n-tls.
Impacted versions: < v1.5.9.
Patches
The patch commit 493b771 is included in s2n-tls v1.5.9 [1]
Workarounds
The 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.
If 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. Please do not create a public GitHub issue.
[1] https://github.com/aws/s2n-tls/releases/tag/v1.5.9 [2] Vulnerability reporting page: https://aws.amazon.com/security/vulnerability-reporting
What each source reports
GitHub AdvisoriesNo score
s2n-tls has undefined behavior at process exit
Impact
s2n-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.
Customers of AWS services do not need to take action. Applications using s2n-tls should upgrade to the most recent release of s2n-tls.
Impacted versions: < v1.5.9.
Patches
The patch commit 493b771 is included in s2n-tls v1.5.9 [1]
Workarounds
The 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.
If 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. Please do not create a public GitHub issue.
[1] https://github.com/aws/s2n-tls/releases/tag/v1.5.9 [2] Vulnerability reporting page: https://aws.amazon.com/security/vulnerability-reporting
- Record
GHSA-rp9h-rf7g-hwgr- Updated
- 2026-11-02
OSVNo score
s2n-tls has undefined behavior at process exit
Impact
s2n-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.
Customers of AWS services do not need to take action. Applications using s2n-tls should upgrade to the most recent release of s2n-tls.
Impacted versions: < v1.5.9.
Patches
The patch commit 493b771 is included in s2n-tls v1.5.9 [1]
Workarounds
The 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.
If 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. Please do not create a public GitHub issue.
[1] https://github.com/aws/s2n-tls/releases/tag/v1.5.9 [2] Vulnerability reporting page: https://aws.amazon.com/security/vulnerability-reporting
- Record
GHSA-rp9h-rf7g-hwgr- Updated
- 2026-11-02
Affected packages
| Package | Affected | Fixed |
|---|---|---|
s2n-tlscrates.io | before 0.3.7 | 0.3.7 |
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | GitHub Advisories, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
GHSA-rp9h-rf7g-hwgr is a vulnerability with no CVSS score yet in s2n-tls, published November 14, 2024. No source lists public exploit code. Fixed in s2n-tls 0.3.7.