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Fencer Intel
medium 4.5

CVE-2026-55798 json

Pillow: WindowsViewer.get_command() OS command injection via unescaped shell path

published 4mo ago modified 17d ago also BIT-pillow-2026-55798 , EUVD-2026-41898 , GHSA-4x4j-2g7c-83w6 , PYSEC-2026-2257

cvss
4.5
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.2%
EPSS 0.2% chance of exploitation in 30 days, percentile 7%
public exploits
0
none known

Summary

Pillow is a Python imaging library. Prior to 12.3.0, WindowsViewer.get_command() constructed a cmd.exe shell command by directly embedding a file path into an f-string without escaping and passed the result to subprocess.Popen(..., shell=True), allowing shell metacharacters in the file path to inject arbitrary cmd.exe commands. This issue is fixed in version 12.3.0.

Patch / fix

  • pypi pillow 12.3.0
  • bitnami pillow 12.3.0
  • python pillow 12.3.0

Is CVE-2026-55798 in your dependencies? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.

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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-2026-55798 updated cvss 4.5

python-pillow: Pillow: Arbitrary command injection via shell metacharacters in file paths

  • Red Hat Exploit Intelligence exploit-intelligence-tech-preview/vulnerability-analysis-rhel9 Red Hat Lightspeed Core lightspeed-core/lightspeed-stack-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-cpu-rhel9, rhaii/vllm-tpu-rhel9, rhaii/vllm-cuda-rhel9, rhaii/vllm-rocm-rhel9, rhaiis/vllm-cpu-rhel9, rhaiis/vllm-tpu-rhel9, +9 more Red Hat Ansible Automation Platform 2 python-pillow 10.3.0-1.el9ap, ansible-automation-platform-26/hub-rhel9, ansible-automation-platform-27/hub-rhel9, ansible-automation-platform/automation-dashboard-rhel9, ansible-automation-platform-25/lightspeed-chatbot-rhel8, ansible-automation-platform-26/lightspeed-chatbot-rhel9, +1 more Red Hat Enterprise Linux 7 python-pillow, python-pillow-qt, python-pillow-tk, python-pillow-sane, python-pillow 10.3.0-1.el9ap
    +5 more products
    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 OpenShift AI (RHOAI) rhoai/odh-automl-rhel9, rhoai/odh-mlflow-rhel9, rhoai/odh-autorag-rhel9, rhoai/odh-caikit-nlp-rhel9, rhoai/odh-vllm-gaudi-rhel9, rhoai/odh-kserve-agent-rhel9, +32 more Red Hat Quay 3 quay/quay-rhel8, quay/quay-rhel9 Red Hat Satellite 6 python-pillow 10.3.0-1.el9ap, python-pillow 12.2.0-1.el8pc
    not affected: vulnerable code not present

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
Proof of concept is public
Automatable
no
Technical impact
partial
Assessed
4mo ago

Exploit prediction

0.18% chance of exploitation in the next 30 days, higher than 7% of all scored CVEs (FIRST EPSS, 2026-11-11).

Exploits and checks

  • github.com https://github.com/python-pillow/Pillow/security/advisories/GHSA-4x4j-2g7c-83w6 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
CNA 3.1 4.5 CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:L/I:L/A:L
GitHub 3.1 4.5 CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:L/I:L/A:L
OSV 3.1 4.5 CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:L/I:L/A:L

Affected packages

ecosystem package affected fixed in
pypi pillow
<12.3.0
12.3.0
bitnami pillow
<12.3.0
12.3.0

Affected products

  • python-pillow Pillow

Classification

Weakness
  • CWE-78 Improper Neutralization of Special Elements used in an OS Command

References

Sources

Fencer Intel 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.

The maintainers of python-pillow/Pillow published their own advisory on GitHub. Reviewed sources take precedence over it.