October 25, 2026

CVE Watchtower

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CVE-2026-115557NVD

Vulnerability Summary

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.
Severity Level
CRITICAL(9.4)
Published Date
Oct 24, 2026
Last Modified
Oct 25, 2026
Exploitation Status
No confirmed exploitation yet
EPSS Score (30-Day)
Data Pending
Root Weakness (CWE)
CWE-299: Unknown/Unlisted Weakness ↗
Refer to the official MITRE database for detailed architectural specifications regarding this weakness.
CVSS v4.0 Base Metrics — Score 9.4 (CRITICAL)
Attack VectorNetwork
Attack ComplexityLow
Attack RequirementsNone
Privileges RequiredNone
User InteractionPassive
Confidentiality (Vulnerable System)High
Integrity (Vulnerable System)High
Availability (Vulnerable System)High
Confidentiality (Subsequent System)High
Integrity (Subsequent System)High
Availability (Subsequent System)High

Affected & Patched Versions

Affected Versions
  • Python Software Foundation CPython < 3.16.0
Patched Versions
  • Python Software Foundation CPython 3.16.0
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🎁7-Day Free Trial — Try Pro or Team, no card required.
📧Email Delivery — Threat intel straight to your inbox.
♾️Unlimited Vendors — Track your entire stack.
🚨All New CVEs — Be the first to know.
📈EPSS Spike Alerts — Catch rising risk before it peaks.
🎯Custom EPSS/CVSS — Filter noise, focus on risk.
🛡️Exploit Intel — A 2nd confirmed-exploit signal beyond KEV.
🐙GitHub Issues — Auto-tracked, no duplicates.
📬Weekly Digest — One clean summary, not inbox spam.
🏷️Watchlist Groups — Tag alerts by team (Infra/AppSec/SOC).
💬Webhooks — Slack & Teams integration.
🔀Smart Routing — Critical alerts to one channel, rest to another.
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External References