CVE-2026-59197: Pillow is a Python imaging library

Q: How do I fix CVE-2026-59197?

pillow: upgrade to 12.3.0. Exact commands for each OS are on this page.

Q: Is CVE-2026-59197 being exploited?

CVE-2026-59197 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

Q: What does CVE-2026-59197 affect?

CVE-2026-59197 affects pillow. Severity is high (CVSS 8.2). Pillow is a Python imaging library. Prior to 12.3.0, Pillow's public rank-filter API can trigger a native heap out-of-bounds write when given a very large odd filter size because ImageFilter.RankFilter.filter() calls image.expand(size // 2,

Q: How urgent is CVE-2026-59197?

Priority 48/100. High severity; Public exploit reference; Remotely exploitable, no login, no user action

This week

HIGH 8.2REMOTEUPGRADE

CVE-2026-59197 is a high-severity flaw (CVSS 8.2) affecting pillow. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

Pillow is a Python imaging library. Prior to 12.3.0, Pillow's public rank-filter API can trigger a native heap out-of-bounds write when given a very large odd filter size because ImageFilter.RankFilter.filter() calls image.expand(size // 2, size // 2) before rank-filter size validation and ImagingExpand() computes output dimensions with unchecked signed int arithmetic. This issue is fixed in version 12.3.0.

Why this priority

High severity
Public exploit reference
Remotely exploitable, no login, no user action

A fixed release or distro patch exists.

Risk facts

CVSS score	8.2 (High)
Attack vector	Network (remote)
Attack complexity	Low
Privileges needed	None
User interaction	None
EPSS exploit chance	0.4% (top 62%)
CISA exploited list	No
Weakness	CWE-190, CWE-787
Published	2026-07-14
Last modified	2026-10-24

Publisher (CNA): GitHub, Inc. · Vendor: python

Last updated 2026-10-24 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2026-07-14 17:17 UTCPublished CVE record published
2026-10-24 21:10 UTCUpdated Record last modified

python pillow UPGRADE

Affected: < 12.3.0

Fixed in: 12.3.0

Safe to downgrade to: no unaffected older release

1. Check installed version

apt-cache policy pillow || rpm -q pillow || pillow --version

2. UPGRADE to 12.3.0 (Debian / Ubuntu)

sudo apt update && sudo apt install --only-upgrade pillow

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade pillow

Note

Distros often backport fixes without changing the version number. Confirm with the distro advisory or changelog.

Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.

Quick answers

How do I fix CVE-2026-59197?

pillow: upgrade to 12.3.0. Exact commands for each OS are on this page.

Is CVE-2026-59197 being exploited?

CVE-2026-59197 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

What does CVE-2026-59197 affect?

CVE-2026-59197 affects pillow. Severity is high (CVSS 8.2). Pillow is a Python imaging library. Prior to 12.3.0, Pillow's public rank-filter API can trigger a native heap out-of-bounds write when given a very large odd filter size because ImageFilter.RankFilter.filter() calls image.expand(size // 2,

How urgent is CVE-2026-59197?

Priority 48/100. High severity; Public exploit reference; Remotely exploitable, no login, no user action

Software pages

Python vulnerabilities

Related CVEs

CVE-2026-54058 CRITICAL 9.1 UPGRADE Pillow is a Python imaging library
CVE-2026-59199 HIGH 7.5 UPGRADE Pillow is a Python imaging library
CVE-2026-59204 HIGH 7.5 UPGRADE Pillow is a Python imaging library
CVE-2026-59205 HIGH 7.5 UPGRADE Pillow is a Python imaging library
CVE-2026-59200 HIGH 7.5 UPGRADE Pillow is a Python imaging library

References

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