CVE-2026-27459
7.2
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
Summary
pyOpenSSL is a Python wrapper around the OpenSSL library. Starting in version 22.0.0 and prior to version 26.0.0, 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. Starting in version 26.0.0, cookie values that are too long are now rejected.
Affected Software
| Vendor | Product | Version Range | Status |
|---|---|---|---|
| pyca | pyopenssl | >= 22.0.0, < 26.0.0 | affected |
Weaknesses
- CWE-120: CWE-120: Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')
ADP Enrichment
CISA ADP Vulnrichment
- SSVC:
- Exploitation: none
- Automatable: no
- Technical Impact: total
pyOpenSSL: DTLS cookie callback buffer overflow
Additional References
- https://access.redhat.com/security/cve/CVE-2026-27459
- https://bugzilla.redhat.com/show_bug.cgi?id=2448503
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-27459.json
- https://access.redhat.com/errata/RHSA-2026:13512
- https://access.redhat.com/errata/RHSA-2026:10754
- https://access.redhat.com/errata/RHSA-2026:14874
- https://access.redhat.com/errata/RHSA-2026:13508
- https://access.redhat.com/errata/RHSA-2026:14873
- https://access.redhat.com/errata/RHSA-2026:14835
- https://access.redhat.com/errata/RHSA-2026:13553
- https://access.redhat.com/errata/RHSA-2026:13545
- https://access.redhat.com/errata/RHSA-2026:7224
- https://access.redhat.com/errata/RHSA-2026:11916
- https://access.redhat.com/errata/RHSA-2026:11856
- https://access.redhat.com/errata/RHSA-2026:21017
- https://access.redhat.com/errata/RHSA-2026:24853
- https://access.redhat.com/errata/RHSA-2026:19375
- https://access.redhat.com/errata/RHSA-2026:22465
- https://access.redhat.com/errata/RHSA-2026:11996
- https://access.redhat.com/errata/RHSA-2026:8437
References
- https://github.com/pyca/pyopenssl/security/advisories/GHSA-5pwr-322w-8jr4
- https://github.com/pyca/pyopenssl/commit/57f09bb4bb051d3bc2a1abd36e9525313d5cd408
- https://github.com/pyca/pyopenssl/blob/358cbf29c4e364c59930e53a270116249581eaa3/CHANGELOG.rst
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