6.5

CVE-2026-96638: Pillow: BMP RLE decoder memory-amplification DoS via unbounded delta escape / absolute mode

Awaiting analysis
AliasesDEBIAN-CVE-2026-96638GHSA-24rc-8hj2-v98cCGA-jx3g-77qj-pq65
Published 21-10-2026Last modified 21-10-2026

Vulnerability summary

CVE-2026-96638 is a medium (CVSS 6.5) Uncontrolled Resource Consumption vulnerability in python-pillow pillow. EPSS estimates a 0.28% chance of exploitation in the next 30 days, higher than 19.4% of scored vulnerabilities.

Overall risk
26/100
0100
Medium · default modelHow is this calculated?
CVSS score
6.5/10
010
Medium · v3.1 (CVE.org)
EPSS score
0.28%
0%100%
Low · Change unavailable
KEVNot listedNot listed by any tracked catalog.
RansomwareNot flaggedNo ransomware use recorded.
Public exploits0No public exploits recorded

Timeline

  1. 21-10-2026
    PublishedVulnerability first disclosed.

Description

Pillow is a Python imaging library. From 9.1.0 until 13.0.0, BmpRleDecoder.decode() in src/PIL/BmpImagePlugin.py permits crafted RLE BMP delta escapes and absolute-mode runs to append beyond the remaining dest_length without a per-branch cap. A delta can add roughly 255 image rows in one iteration, so a kilobyte-sized file with a large but permitted width can expand the data bytearray to hundreds of megabytes or more, causing memory-exhaustion denial of service. This issue is fixed in version 13.0.0.

CVSS metrics

5 scores · 5 sources · 1 version

EPSS trend

Probability

0.28%

Chance of exploitation in the next 30 days

Percentile

19%

Versus all other CVEs

30-day change

Change unavailable

Change unavailable

22-10-202623-10-2026

Known exploited

Compare KEV catalogs
CISA KEV

Not in the CISA KEV catalog.

ENISA CNW

Not in the ENISA CNW catalog.

CIRCL

Not in the CIRCL catalog.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Chainguard12 products
  • mlflowAll versions (No fix recorded)
  • mlflow-fipsAll versions (No fix recorded)
  • nemo-gymAll versions (No fix recorded)
  • nemo-rl-cuda-13.0-automodelAll versions (No fix recorded)
  • open-webuiAll versions (No fix recorded)
Ubuntu2 products
  • pillowAll versions (No fix recorded)
  • pillow-python2All versions (No fix recorded)
Wolfi2 products
  • mlflowAll versions (No fix recorded)
  • open-webuiAll versions (No fix recorded)
Debian1 product
  • pillowAll versions (No fix recorded)
PyPI1 product
  • pillow≥ 9.1.0, < 13.0.0
Python-pillow1 product

6 vendors · 19 products

References

10 links