Red Hat Security AdvisoryRHSA-2026:76945
python3.9 security update
Released 2026-10-06 · Red Hat rating Important · View on Red Hat →
Fixed in
- Red Hat Enterprise Linux AppStream E4S (v.9.2) python-unversioned-command-3.9.16-1.el9_2.15, python3-devel-3.9.16-1.el9_2.15, python3-tkinter-3.9.16-1.el9_2.15
- Red Hat Enterprise Linux BaseOS E4S (v.9.2) python3-3.9.16-1.el9_2.15, python3-libs-3.9.16-1.el9_2.15, python3.9-3.9.16-1.el9_2.15
Fixes 3 records
Priority MEDIUM 45
The incremental HTML parser (html.parser.HTMLParser) allows for CPU denial-of-service through repeated unterminated markup declarations when processing uncontrolled data.
CVSS 4.0HIGH 8.7· Network · No auth · No interaction · EPSS 0.00637 · Published 2026-07-09 · Partial fix · 3.10.21, 3.11.16 +4 CWE-400
Priority LOW 21
The html.parser.HTMLParser class had worse-case quadratic complexity when processing certain crafted malformed inputs potentially leading to amplified denial-of-service.
CVSS 3.1MEDIUM 4.3· Network · Low privileges · No interaction · EPSS 0.00603 · Published 2025-06-17 · Partial fix · 3.9.24, 3.10.19 +4 CWE-1333
Priority LOW 9
If the value passed to os.path.expandvars() is user-controlled a performance degradation is possible when expanding environment variables.
CVSS 4.0LOW 1.8· Local · High privileges · No interaction · EPSS 0.00149 · Published 2025-10-31 · Partial fix · 3.9.25, 3.10.20 +5 CWE-400
