GHSA-5pwr-322w-8jr4
pyOpenSSL DTLS cookie callback buffer overflow
At a glance
- Published
- Updated
- CVE
- CVE-2026-27459
- Aliases
- PYSEC-2026-2269
- CVSS_V4
- CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U
Description
If a user provided callback to `set_cookie_generate_callback` returned a cookie value greater than 256 bytes, pyOpenSSL would overflow an OpenSSL provided buffer. Cookie values that are too long are now rejected.
Affected packages
| Package | Versions |
|---|---|
| PyPI · pyopenssl | introduced 22.0.0, fixed 26.0.0 |
References
- https://github.com/pyca/pyopenssl/security/advisories/GHSA-5pwr-322w-8jr4 WEB
- https://nvd.nist.gov/vuln/detail/CVE-2026-27459 ADVISORY
- https://github.com/pyca/pyopenssl/commit/57f09bb4bb051d3bc2a1abd36e9525313d5cd408 WEB
- https://github.com/pyca/pyopenssl PACKAGE
- https://github.com/pyca/pyopenssl/blob/358cbf29c4e364c59930e53a270116249581eaa3/CHANGELOG.rst WEB
Sources
| Source | Licence |
|---|---|
| OSV.dev | CC-BY 4.0 — GitHub Advisory Database |