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TI-2026-12885 Aliases CVE-2026-15310GHSA-xj79-6hh5-9w6q

zipfile: bzip2/LZMA/Zstandard members decompress without a max_length bound, defeating chunked-read memory limits

Priority LOW 12CWE-400Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
Active
Attack complexity
Low
Attack requirements
Present
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · Low
Fix status
Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA and Red Hat. Impact type from CWE-400.

Summary

When decompressing crafted zip files using the bzip/LZMA/Zstandard compressions, Python could use an attacker-controlled size to pre-allocate memory, possibly resulting in memory exhaustion.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00526 44th percentileScored 2026-11-07
Fix Fixed CPython (Python Software Foundation): 3.10.22, 3.11.17, 3.12.15 +3Red Hat: 5 advisories

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 3.10.22; 3.11.0 to before 3.11.17; 3.12.0 to before 3.12.15; 3.13.0 to before 3.13.16; 3.14.0 to before 3.14.8; 3.15.0a1 to before 3.15.0rc23.10.22, 3.11.17, 3.12.15, 3.13.16, 3.14.8, 3.15.0rc2Patch availableCNA
  • CPython VendorPython Software Foundation Affected before 3.10.22; 3.11.0 to before 3.11.17; 3.12.0 to before 3.12.15; 3.13.0 to before 3.13.16; 3.14.0 to before 3.14.8; 3.15.0a1 to before 3.15.0rc2 Fixed in 3.10.22, 3.11.17, 3.12.15, 3.13.16, 3.14.8, 3.15.0rc2 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 3.10.22, 3.11.17, 3.12.15, 3.13.16, 3.14.8, 3.15.0rc2

Red Hat 5 advisories

  • RHSA-2026:65567 Released 2026-09-08 · Red Hat rating Moderate
    Red Hat Hardened Images RPMs Security Update
    • Red Hat Hardened Images python3.13-3.13.15-1.1.hum1@aarch64, python3.13-3.13.15-1.1.hum1@src, python3.13-3.13.15-1.1.hum1@x86_64 +16
  • RHSA-2026:65531 Released 2026-09-08 · Red Hat rating Moderate
    Red Hat Hardened Images RPMs Security Update
    • Red Hat Hardened Images python3.12-3.12.14-1.1.hum1@aarch64, python3.12-3.12.14-1.1.hum1@src, python3.12-3.12.14-1.1.hum1@x86_64 +12
  • RHSA-2026:65525 Released 2026-09-08 · Red Hat rating Moderate
    Red Hat Hardened Images RPMs Security Update
    • Red Hat Hardened Images python3.11-3.11.16-1.2.hum1@aarch64, python3.11-3.11.16-1.2.hum1@src, python3.11-3.11.16-1.2.hum1@x86_64 +12
Show 2 more Red Hat advisories
  • RHSA-2026:65513 Released 2026-09-08 · Red Hat rating Moderate
    Red Hat Hardened Images RPMs Security Update
    • Red Hat Hardened Images python3.10-3.10.21-1.1.hum1@aarch64, python3.10-3.10.21-1.1.hum1@src, python3.10-3.10.21-1.1.hum1@x86_64 +12
  • RHSA-2026:65505 Released 2026-09-08 · Red Hat rating Important
    Red Hat Hardened Images RPMs Security Update
    • Red Hat Hardened Images python-unversioned-command-3.14.7-1.1.hum1@noarch@public-hummingbird-aarch64-rpms, python-unversioned-command-3.14.7-1.1.hum1@noarch@public-hummingbird-x86_64-rpms, python3-3.14.7-1.1.hum1@aarch64 +28

Vendor assessments

Red Hat

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

ProductStatusPlan or fix
Red Hat Hardened ImagesFixed RHSA-2026:65505, RHSA-2026:65513, RHSA-2026:65525, RHSA-2026:65531, RHSA-2026:65567
Not affected: 1 product
  • Red Hat Hardened Images

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-15310
  2. 2026-10-03 Alias added: GHSA-xj79-6hh5-9w6q
  3. 2026-10-18 Fix available: RHSA-2026:65531 · Red Hat
  4. 2026-10-18 Fix available: RHSA-2026:65567 · Red Hat
  5. 2026-10-18 Fix available: RHSA-2026:65505 · Red Hat
  6. 2026-10-18 Fix available: RHSA-2026:65513 · Red Hat
  7. 2026-10-18 Fix available: RHSA-2026:65525 · Red Hat
  8. 2026-10-18 Fix available: Red Hat Hardened Images · Red Hat
  9. 2026-10-18 CVSS score added · Red Hat

References

Patch 11

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