CVE-2026-115557
CPython: Distrust compromised intermediate certificates in ssl module
Python Software Foundation CPythonRuntimes & languagesCVSS
9.4CriticalExploitationNo known exploitationNot in CISA KEV, which does not prove it is unexploitedCISA KEV
Exploit odds (EPSS)No scoreNo FIRST EPSS score in this snapshot yet
Fixed inNone listedNo source names a fixed version. Check the vendor advisory below
What fixes it
No source in this snapshot names a fixed version. The vendor advisories under References are the place to check.
Reports 5
2 outlets mention it. Reports are not confirmation; each links to its source.
- @infosec.skyfleet.blue: [oss-security][CVE-2026-115557] Distrust compromised intermediate certificates in Python ssl moduleBluesky: CVE posts, 24 Oct 2026
- @cve.skyfleet.blue: CVE-2026-115557 - Distrust compromised intermediate certificates in ssl module CVE ID : CVE-2026-115557 Published : Oct. 24, 2026, 3:17 p.m. | 42 minutes ago Description : Python hBluesky: CVE posts, 24 Oct 2026
- [oss-security][CVE-2026-115557] Distrust compromised intermediate certificates in Python ssl moduleoss-security, 24 Oct 2026
- @stackflag.bsky.social: CVE-2026-115557 - cpython The Python programming language now blocks any SSL/TLS certificates that have been identified as compromised, even if your system isn’t set up to check foBluesky: CVE posts, 24 Oct 2026
- @stemshop.bsky.social: 🚨 CVE-2026-115557 — CVSS 9.4 CRITICAL Python has added a denylist for known compromised certificates to the "ssl" module to ensure user safety ev... 🔎 https://stemshop.top/cve/CVE-Bluesky: CVE posts, 24 Oct 2026
Description
Python has added a denylist for known compromised certificates to the "ssl" module to ensure user safety even without certificate revocation configured. Known compromised certificates will automatically be rejected regardless of the SSLContext policy configuration.
Text from CVE List
Affected versions 1
- CPythonaffected: all versions through 3.16.0CVE List