CVE-2026-1299 Affecting python3.11-libs package, versions <0:3.11.13-5.1.el9_7


Severity

Recommended
medium

Based on Rocky Linux security rating.

Threat Intelligence

EPSS
0.05% (14th percentile)

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  • Snyk IDSNYK-ROCKY9-PYTHON311LIBS-15564743
  • published14 Mar 2026
  • disclosed23 Jan 2026

Introduced: 23 Jan 2026

CVE-2026-1299  (opens in a new tab)

How to fix?

Upgrade Rocky-Linux:9 python3.11-libs to version 0:3.11.13-5.1.el9_7 or higher.
This issue was patched in RLSA-2026:4216.

NVD Description

Note: Versions mentioned in the description apply only to the upstream python3.11-libs package and not the python3.11-libs package as distributed by Rocky-Linux. See How to fix? for Rocky-Linux:9 relevant fixed versions and status.

The email module, specifically the "BytesGenerator" class, didn’t properly quote newlines for email headers when serializing an email message allowing for header injection when an email is serialized. This is only applicable if using "LiteralHeader" writing headers that don't respect email folding rules, the new behavior will reject the incorrectly folded headers in "BytesGenerator".

CVSS Base Scores

version 3.1