{"id":"CVE-2026-96638","summary":"Pillow: BMP RLE decoder memory-amplification DoS via unbounded delta escape / absolute mode","details":"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.","aliases":["GHSA-24rc-8hj2-v98c"],"modified":"2026-10-23T02:45:26.416800552Z","published":"2026-10-21T20:47:21.767Z","database_specific":{"cwe_ids":["CWE-400","CWE-770"],"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/96xxx/CVE-2026-96638.json","cna_assigner":"GitHub_M"},"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/96xxx/CVE-2026-96638.json"},{"type":"FIX","url":"https://github.com/python-pillow/Pillow/commit/e7794835e323ff2691d9b3a974cade1a44301b9a"},{"type":"FIX","url":"https://github.com/python-pillow/Pillow/pull/10015"},{"type":"WEB","url":"https://github.com/python-pillow/Pillow/releases/tag/13.0.0"},{"type":"ADVISORY","url":"https://github.com/python-pillow/Pillow/security/advisories/GHSA-24rc-8hj2-v98c"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-96638"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/python-pillow/pillow","events":[{"introduced":"5d070222d21138d2ead002fd33fdf5adcb708941"},{"fixed":"293218ad059d994baf1777d882911bed6a49704a"},{"fixed":"e7794835e323ff2691d9b3a974cade1a44301b9a"}],"database_specific":{"extracted_events":[{"range":[{"introduced":"9.1.0"},{"fixed":"13.0.0"}],"source":"AFFECTED_FIELD","strategy":"StringRangeExpression"},{"range":[{"fixed":"e7794835e323ff2691d9b3a974cade1a44301b9a"}],"source":"REFERENCES_COMMIT"},{"range":[{"fixed":"293218ad059d994baf1777d882911bed6a49704a"}],"source":"REFERENCES_TAG","original_tag":"13.0.0"}]}}],"versions":["12.3.0","12.2.0","12.1.0","12.0.0","11.3.0","11.2.1","11.1.0","11.0.0","10.4.0","10.3.0","10.2.0","10.1.0","10.0.0","9.5.0","9.4.0","9.3.0","9.2.0","9.1.0"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-96638.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H"}]}