CVE-2026-96638
Pillow: BMP RLE decoder memory-amplification DoS via unbounded delta escape / absolute mode
CVSS Score
6.5
EPSS Score
0.0%
EPSS Percentile
0th
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.
| CWE | CWE-400 CWE-770 |
| Vendor | python-pillow |
| Product | pillow |
| Published | Oct 21, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
Required
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High
Affected Versions
python-pillow / Pillow
>= 9.1.0, < 13.0.0
References
github.com: https://github.com/python-pillow/Pillow/security/advisories/GHSA-24rc-8hj2-v98c github.com: https://github.com/python-pillow/Pillow/pull/10015 github.com: https://github.com/python-pillow/Pillow/commit/e7794835e323ff2691d9b3a974cade1a44301b9a github.com: https://github.com/python-pillow/Pillow/releases/tag/13.0.0