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Fencer Vulns
medium 5.9

CVE-2026-112396 json

Pillow: Heap use-after-free when encoding TIFF to an in-memory buffer

published 2026-10-19 20 d ago modified 2026-10-27 12 d ago also BIT-pillow-2026-112396 , EUVD-2026-104632 , GHSA-4rr5-89j8-mwwm , PYSEC-2026-4328

cvss
5.9
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.7%
EPSS 0.7% chance of exploitation in 30 days, percentile 53%
public exploits
0
none known

Summary

Pillow is a Python imaging library. From 11.3.0 until 13.0.0, Pillow has a heap use-after-free when libtiff rejects a tag while encoding TIFF data to an in-memory buffer. When an application saves attacker-influenced TIFF tags to BytesIO, libtiff can reject a tag during encoding in ImagingLibTiffEncode; the error path then frees the output buffer without closing or clearing the TIFF handle, and later cleanup flushes through the write callback into freed memory, which can crash the process and may enable code execution. This issue is fixed in version 13.0.0.

Patch / fix

  • pypi pillow 13.0.0
  • bitnami pillow 13.0.0
  • python pillow 13.0.0
  • python-Pillow openSUSE Tumbleweed 13.0.0-1.1

opensuse advisories openSUSE-SU-2026:12230-1

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2026-112396 updated cvss 5.9

pillow: pillow: arbitrary code execution via heap use-after-free during TIFF encoding

  • Red Hat Exploit Intelligence exploit-intelligence/vulnerability-analysis-rhel9
    affected: no fix planned “Out of support scope”
  • Red Hat Lightspeed Core lightspeed-core/rag-tool-cpu-rhel9, lightspeed-core/lightspeed-stack-rhel9, lightspeed-core/rag-tool-cuda-12.9-rhel9 Red Hat OpenShift Lightspeed openshift-lightspeed/lightspeed-ocp-rag-rhel9, openshift-lightspeed/lightspeed-service-api-rhel9, openshift-lightspeed-tech-preview/lightspeed-rag-tool-rhel9 Red Hat AI Inference Server rhaii/vllm-tpu-rhel9, rhaiis/vllm-cpu-rhel9, rhaiis/vllm-tpu-rhel9, rhaiis/vllm-cuda-rhel9, rhaiis/vllm-rocm-rhel9, rhaii/vllm-neuron-rhel9, +3 more
    affected: no fix available “Fix deferred”
  • Red Hat Ansible Automation Platform 2 python-pillow 10.3.0-1.el9ap, python3x-pillow 10.3.0-1.el8ap, python3.11-pillow 10.3.0-1.el8ap, python3.12-pillow 12.3.0-1.el9ap, ansible-automation-platform-26/hub-rhel9, ansible-automation-platform-27/hub-rhel9, +4 more
    affected: no fix available, no fix planned “Out of support scope”
  • Red Hat Enterprise Linux 8 python3-pillow, python3-pillow-tk, python-pillow 10.3.0-1.el9ap Red Hat Enterprise Linux AI (RHEL AI) 3 rhelai3/bootc-cuda-rhel9, rhelai3/bootc-rocm-rhel9, rhelai3/bootc-gaudi-rhel9, rhelai3/bootc-aws-cuda-rhel9, rhelai3/bootc-gcp-cuda-rhel9, rhelai3/disk-image-cuda-rhel9, +2 more Red Hat Lightspeed Services for OCP lightspeed-services-ocp/ocp-rules-rhel9 Red Hat OpenShift AI (RHOAI) rhai/guidellm-rhel9, rhoai/odh-automl-rhel9, rhoai/odh-mlflow-rhel9, rhoai/odh-autorag-rhel9, rhoai/odh-ogx-core-rhel9, rhoai/odh-vllm-gaudi-rhel9, +38 more
    affected: no fix available “Fix deferred”
  • Red Hat Quay 3 quay/quay-rhel8, quay/quay-rhel9
    affected: no fix available, no fix planned “Out of support scope”
  • Red Hat Satellite 6 python-pillow 10.3.0-1.el9ap, python3.12-pillow 12.3.0-1.el9ap
    affected: no fix available “Fix deferred”
  • Red Hat AI Inference Server 3.5 rhaii/vllm-cpu-rhel9 1793444554, rhaii/vllm-cuda-rhel9 1793444600, rhaii/vllm-rocm-rhel9 1793444456, rhaii/vllm-gaudi-rhel9 1793444510, rhaii/vllm-spyre-rhel9 1793444409, rhaii/model-opt-cuda-rhel9 1793444339
    fixed: vendor fix RHSA-2026:94715

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation
none
Automatable
no
Technical impact
partial
Assessed
19 d ago

Exploit prediction

0.69% chance of exploitation in the next 30 days, higher than 53% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

  • github.com https://github.com/python-pillow/Pillow/security/advisories/GHSA-4rr5-89j8-mwwm referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
CNA 3.1 5.9 CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
GitHub 3.1 5.9 CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
NVD 3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
OSV 3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Affected packages

ecosystem package affected fixed in
pypi pillow
>=11.3.0, <13.0.0
13.0.0
bitnami pillow
>=11.3.0, <13.0.0
13.0.0

Affected products

  • python-pillow Pillow

Classification

Weakness

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.