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TI-2026-02828 Aliases CVE-2026-3276GHSA-jg6j-874m-wgjj

Potential DoS via quadratic complexity in unicodedata.normalize()

Priority LOW 29CWE-407Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Attack requirements
Present
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · Low
Fix status
Partial Red Hat: 1 fixed, 9 without a fix

Attack profile from CVSS 4.0 · CNA. Fix status from CNA and Red Hat. Impact type from CWE-407.

Summary

unicodedata.normalize() can take excessive CPU time when processing specially crafted Unicode input containing long runs of combining characters with alternating Canonical Combining Class values. This affects all normalization forms.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00486 42nd percentileScored 2026-11-07
Fix Partial CPython (Python Software Foundation): 3.10.21, 3.11.16, 3.12.14 +3Red Hat: 5 advisoriesRed Hat: 1 fixed, 9 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
Python Software FoundationCPythonbefore 3.10.21; 3.11.0 to before 3.11.16; 3.12.0 to before 3.12.14; 3.13.0 to before 3.13.14; 3.14.0 to before 3.14.6; 3.15.0a1 to before 3.15.0b23.10.21, 3.11.16, 3.12.14, 3.13.14, 3.14.6, 3.15.0b2Patch availableCNA
  • CPython VendorPython Software Foundation Affected before 3.10.21; 3.11.0 to before 3.11.16; 3.12.0 to before 3.12.14; 3.13.0 to before 3.13.14; 3.14.0 to before 3.14.6; 3.15.0a1 to before 3.15.0b2 Fixed in 3.10.21, 3.11.16, 3.12.14, 3.13.14, 3.14.6, 3.15.0b2 Patch available CNA

CPE names Threatist (inferred) · 1

Inferred from how NVD named this product before; not given by a source.

CPEVersionsRoleVendor
cpe:2.3:a:python:python:*:*:*:*:*:*:*:*——python-pillow
  • cpe:2.3:a:python:python:*:*:*:*:*:*:*:* Versions — — ·python-pillow

Remediation

  • Fix · CNA CPython (Python Software Foundation) Fixed in 3.10.21, 3.11.16, 3.12.14, 3.13.14, 3.14.6, 3.15.0b2

Red Hat 5 advisories

  • RHSA-2026:68309 Released 2026-09-16 · Red Hat rating Important
    Red Hat Hardened Images RPMs Security Update
    • Red Hat Hardened Images python3.13-3.13.15-1.3.hum1@aarch64, python3.13-3.13.15-1.3.hum1@src, python3.13-3.13.15-1.3.hum1@x86_64 +16
  • RHSA-2026:68154 Released 2026-09-16 · Red Hat rating Important
    Red Hat Hardened Images RPMs Security Update
    • Red Hat Hardened Images python3.12-3.12.14-1.3.hum1@aarch64, python3.12-3.12.14-1.3.hum1@src, python3.12-3.12.14-1.3.hum1@x86_64 +12
  • RHSA-2026:68135 Released 2026-09-16 · Red Hat rating Important
    Red Hat Hardened Images RPMs Security Update
    • Red Hat Hardened Images python3.11-3.11.16-1.4.hum1@aarch64, python3.11-3.11.16-1.4.hum1@src, python3.11-3.11.16-1.4.hum1@x86_64 +12
Show 2 more Red Hat advisories
  • RHSA-2026:68132 Released 2026-09-16 · Red Hat rating Important
    Red Hat Hardened Images RPMs Security Update
    • Red Hat Hardened Images python3.10-3.10.21-1.3.hum1@aarch64, python3.10-3.10.21-1.3.hum1@src, python3.10-3.10.21-1.3.hum1@x86_64 +12
  • RHSA-2026:67572 Released 2026-09-15 · Red Hat rating Important
    Red Hat Hardened Images RPMs Security Update
    • Red Hat Hardened Images python-unversioned-command-3.14.7-1.2.hum1@noarch@public-hummingbird-aarch64-rpms, python-unversioned-command-3.14.7-1.2.hum1@noarch@public-hummingbird-x86_64-rpms, python3-3.14.7-1.2.hum1@aarch64 +28

Vendor assessments

Red Hat

Red Hat rating: Moderate. Red Hat's page for this CVE →

ProductStatusPlan or fix
Exploit IntelligenceAffectedNo fix yet: Fix deferred
Red Hat AI Inference ServerAffectedNo fix yet: Fix deferred
Red Hat Enterprise Linux 10AffectedNo fix yet: Fix deferred
Red Hat Enterprise Linux 6AffectedNo fix yet: Fix deferred
Red Hat Enterprise Linux 7AffectedNo fix yet: Fix deferred
Red Hat Enterprise Linux 8AffectedNo fix yet: Fix deferred
Red Hat Enterprise Linux 9AffectedNo fix yet: Fix deferred
Red Hat Enterprise Linux AI (RHEL AI) 3AffectedNo fix yet: Fix deferred
Red Hat OpenShift AI (RHOAI)AffectedNo fix yet: Fix deferred
Red Hat Hardened ImagesFixed RHSA-2026:67572, RHSA-2026:68132, RHSA-2026:68135, RHSA-2026:68154, RHSA-2026:68309
Not affected: 1 product
  • Red Hat Hardened Images

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-3276
  2. 2026-10-03 Alias added: GHSA-jg6j-874m-wgjj
  3. 2026-10-09 EPSS moved to the below the 50th percentile

References

Patch 9

Advisory 1

Other 1

  • TI-2024-07037 Quadratic complexity parsing cookies with backslashes CVSS 3.1HIGH 7.5
  • TI-2024-11791 Bypass extraction filter to modify file metadata outside extraction directory CVSS 3.1MEDIUM 5.3
  • TI-2024-00411 Quoted zip-bomb protection for zipfile CVSS 3.1MEDIUM 6.2
  • TI-2026-13296 `HTTPPasswordMgr` can send saved HTTPS credentials via HTTP because of incorrect scheme matching CVSS 4.0MEDIUM 6.0
  • TI-2024-06422 Email header injection due to unquoted newlines CVSS 3.1MEDIUM 5.5
  • TI-2026-04606 Possible to hijack modules in current working directory CVSS 4.0MEDIUM 5.6
See all 83 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences