DEBIAN-CVE-2026-27459

Advisory lineage Upstream: 1 Downstream: 0
Upstream
CVE-2026-27459
Published: 18 Mar 2026, 00:16
Last modified:11 Jul 2026, 21:00

Vulnerability Summary

Overall Risk (default)
high
70/100
CVSS Score
9.8 CRITICAL
3.1 (osv_debian)
EPSS Score
No data
KEV
Not listed
Ransomware
No reports
Public exploits
None found
Dark Web
Not detected

Timeline

18 Mar 2026, 00:16
Published
Vulnerability first disclosed
11 Jul 2026, 21:00
Last Modified
Vulnerability information updated

Description

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.

CVSS Metrics

  • v3.1•CRITICAL•Score: 9.8CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Affected Systems

  • debian•pyopenssl

    all | all | all | all | < 25.0.0-1+deb13u1 | < 26.0.0-1

References (1)