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TI-2026-79011 Aliases CVE-2026-114501GHSA-654x-cwwv-5j9c

Pillow Arrow export leaks stale heap memory when alignment is set

Priority HIGH 67CWE-226Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Attack requirements
Present
Impact type
Information disclosure
Confidentiality · integrity · availability
Low · None · None
Fix status
Partial Red Hat: 1 fixed, 11 without a fix

Attack profile from CVSS 4.0 · CNA. Fix status from CNA, GitHub and Red Hat. Impact type from CWE-908 and the CVSS impact.

Summary

Pillow versions from 11.2.1 before 13.0.0 are affected. Arrow export assumes that image rows are tightly contiguous, so it exports from the wrong buffer position when PILLOW_ALIGNMENT adds row padding (CWE-908). Applications that configure alignment and export images to Arrow can disclose one user's pixels or other process memory to another user.

Written with Claude Haiku 5.5 from the sources below · 2026-11-04

Description from the CNA

Pillow is a Python imaging library. From 11.2.1 until 13.0.0, Arrow export assumes that an image's rows are tightly contiguous and exports from im->blocks[0].ptr even when PILLOW_ALIGNMENT makes aligned_linesize include row padding or an aligned offset before the first row. The resulting Arrow buffer can include uninitialized padding, bytes preceding the first row, or stale heap contents from previously freed images. Applications that configure alignment and export images to Arrow can therefore disclose one user's pixels or other process memory to another user. This issue is fixed in version 13.0.0.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.0037 31st percentileScored 2026-11-07
Fix Partial Pillow (python-pillow): 13.0.0Pillow (PyPI): 13.0.0Red Hat: 6 advisoriesRed Hat: 1 fixed, 11 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
Yes
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-pillowPillow11.2.1 to before 13.0.013.0.0Patch availableCNA
—Pillow (PyPI)11.2.1 to before 13.0.013.0.0Patch availableGHSA-654x-cwwv-5j9c
  • Pillow Vendorpython-pillow Affected 11.2.1 to before 13.0.0 Fixed in 13.0.0 Patch available CNA
  • Pillow (PyPI) Vendor— Affected 11.2.1 to before 13.0.0 Fixed in 13.0.0 Patch available GHSA-654x-cwwv-5j9c

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:python:pillow:*:*:*:*:*:*:*:*11.2.1 to before 13.0.0Vulnerablepython-pillow
  • cpe:2.3:a:python:pillow:*:*:*:*:*:*:*:* Versions 11.2.1 to before 13.0.0 Vulnerable ·python-pillow

Remediation

Upgrade Pillow to version 13.0.0 or later, which fixes the PyPI package. Red Hat AI Inference Server 3.5 is fixed by RHSA-2026:94738, RHSA-2026:94721, RHSA-2026:94717, RHSA-2026:94715, RHSA-2026:94709 and RHSA-2026:94702. Red Hat lists Exploit Intelligence with no fix planned, and lists Lightspeed Core, OpenShift Lightspeed, Red Hat Enterprise Linux 8 and other products as affected without a fix.

Written with Claude Haiku 5.5 from the sources below · 2026-11-04

  • Fix · CNA Pillow (python-pillow) Fixed in 13.0.0
  • Fix · GHSA-654x-cwwv-5j9c Pillow (PyPI) Fixed in 13.0.0 Advisory →

Red Hat 6 advisories

  • RHSA-2026:94738 Released 2026-11-03 · Red Hat rating Critical
    Red Hat AI Inference 3.5.3 (CUDA)
    • Red Hat AI Inference Server 3.5 registry.redhat.io/rhaii/vllm-cuda-rhel9
  • RHSA-2026:94721 Released 2026-11-03 · Red Hat rating Critical
    Red Hat AI Inference Tech Preview 3.5.3 (Gaudi)
    • Red Hat AI Inference Server 3.5 registry.redhat.io/rhaii/vllm-gaudi-rhel9
  • RHSA-2026:94717 Released 2026-11-03 · Red Hat rating Critical
    Red Hat AI Inference 3.5.3 (Spyre)
    • Red Hat AI Inference Server 3.5 registry.redhat.io/rhaii/vllm-spyre-rhel9
Show 3 more Red Hat advisories
  • RHSA-2026:94715 Released 2026-11-03 · Red Hat rating Critical
    Red Hat AI Inference Model Optimization Tools 3.5.3 (CUDA)
    • Red Hat AI Inference Server 3.5 registry.redhat.io/rhaii/model-opt-cuda-rhel9
  • RHSA-2026:94709 Released 2026-11-03 · Red Hat rating Critical
    Red Hat AI Inference 3.5.3 (ROCm)
    • Red Hat AI Inference Server 3.5 registry.redhat.io/rhaii/vllm-rocm-rhel9
  • RHSA-2026:94702 Released 2026-11-03 · Red Hat rating Critical
    Red Hat AI Inference 3.5.3 (CPU)
    • Red Hat AI Inference Server 3.5 registry.redhat.io/rhaii/vllm-cpu-rhel9

Vendor assessments

Red Hat

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

ProductStatusPlan or fix
Exploit IntelligenceAffectedNo fix planned: Out of support scope
Lightspeed CoreAffectedNo fix yet: Fix deferred
OpenShift LightspeedAffectedNo fix yet: Fix deferred
Red Hat AI Inference ServerAffectedNo fix yet: Fix deferred
Red Hat Ansible Automation Platform 2AffectedNo fix yet: Fix deferred
Red Hat Enterprise Linux 8AffectedNo fix yet: Fix deferred
Red Hat Enterprise Linux AI (RHEL AI) 3AffectedNo fix yet: Fix deferred
Red Hat Lightspeed Services for OCPAffectedNo fix yet: Fix deferred
Red Hat OpenShift AI (RHOAI)AffectedNo fix yet: Fix deferred
Red Hat Quay 3AffectedNo fix yet: Fix deferred
Red Hat Satellite 6AffectedNo fix yet: Fix deferred
Red Hat AI Inference Server 3.5Fixed RHSA-2026:94702, RHSA-2026:94709, RHSA-2026:94715, RHSA-2026:94717, RHSA-2026:94721, RHSA-2026:94738

Timeline

  1. 2026-10-21 Threatist record created from CVE-2026-114501
  2. 2026-10-23 Affected versions changed · Red Hat
  3. 2026-10-23 CVSS score added · Red Hat
  4. 2026-10-23 Priority changed: MEDIUM → LOW
  5. 2026-10-23 Alias added: GHSA-654x-cwwv-5j9c
  6. 2026-10-23 Fix available: PyPI/[email protected] · GHSA-654x-cwwv-5j9c
  7. 2026-10-23 CVSS score added · GHSA-654x-cwwv-5j9c
  8. 2026-10-23 Weakness changed · GHSA-654x-cwwv-5j9c
  9. 2026-10-23 6 new references · GHSA-654x-cwwv-5j9c
  10. 2026-10-27 CVSS score added · NVD
  11. 2026-10-30 CISA SSVC decision points changed
  12. 2026-10-30 Priority changed: LOW → HIGH
  13. 2026-11-04 Fix available: RHSA-2026:94717 · Red Hat
  14. 2026-11-04 Fix available: RHSA-2026:94715 · Red Hat
  15. 2026-11-04 Fix available: RHSA-2026:94709 · Red Hat
  16. 2026-11-04 Fix available: RHSA-2026:94738 · Red Hat
  17. 2026-11-04 Fix available: RHSA-2026:94702 · Red Hat
  18. 2026-11-04 Fix available: RHSA-2026:94721 · Red Hat
  19. 2026-11-04 Fix available: Red Hat AI Inference Server 3.5 · Red Hat

References

Patch 1

Advisory 2

Other 3

  • TI-2026-76627 Out-of-bounds read in Pillow TIFF encoder ColorMap handling CVSS 4.0HIGH 8.8
  • TI-2026-76625 Quadratic-time denial of service in Pillow PDF save_all CVSS 4.0HIGH 8.7
  • TI-2026-76605 NULL pointer dereference in Pillow's Image.merge function CVSS 4.0HIGH 8.7
  • TI-2026-76604 Out-of-bounds read in Pillow TIFF decoding leaks heap memory CVSS 4.0HIGH 8.8
  • TI-2026-76602 Double free in Pillow ImagingScaleAffine on allocation failure CVSS 4.0HIGH 8.7
  • TI-2026-76600 GIF seek in Pillow keeps rejected size, allowing denial of service CVSS 4.0HIGH 8.7
See all 110 →

Sources

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