{"id":"CVE-2026-42309","aliases":["GHSA-5xmw-vc9v-4wf2","BIT-pillow-2026-42309","PYSEC-2026-2251"],"title":"Pillow has a heap buffer overflow with nested list coordinates","summary":"Pillow has a heap buffer overflow with nested list coordinates","severity":"medium","cvss":5.5,"cvssVector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","vendor":"pillow","product":"pillow","ecosystem":"pip","affected":["pillow >= 11.2.1, < 12.2.0"],"patched":["pillow 12.2.0"],"published":"2026-05-04","updated":"2026-10-19","sourceUpdated":"2026-10-19T20:00:04.709097863Z","source":"OSV","sourceUrl":"https://osv.dev/vulnerability/GHSA-5xmw-vc9v-4wf2","references":[{"url":"https://github.com/python-pillow/Pillow/security/advisories/GHSA-5xmw-vc9v-4wf2"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-42309"},{"url":"https://github.com/designcomputer/mysql_mcp_server/commit/a96549f4a4d65443fd6e9c7f2324fba9a5c80a82"},{"url":"https://github.com/python-pillow/Pillow/commit/cf6de8ca9b23e714aa5310e1c791eda66fc0b670"},{"url":"https://github.com/pypa/advisory-database/tree/main/vulns/pillow/PYSEC-2026-2251.yaml"},{"url":"https://github.com/python-pillow/Pillow"},{"url":"https://github.com/python-pillow/Pillow/releases/tag/12.2.0"},{"url":"https://github.com/advisories/GHSA-5xmw-vc9v-4wf2"},{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-42309.json"},{"url":"https://access.redhat.com/security/cve/CVE-2026-42309"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2468458"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-42309"},{"url":"https://access.redhat.com/errata/RHSA-2026:16008"},{"url":"https://access.redhat.com/errata/RHSA-2026:16030"},{"url":"https://access.redhat.com/errata/RHSA-2026:16009"},{"url":"https://access.redhat.com/errata/RHSA-2026:57387"}],"tags":["osv","pip","ghsa","csaf","vex","red-hat"],"epss":0.00133,"epssPercentile":0.02785,"cwe":["CWE-122","CWE-131"],"scores":{"osv":5.5,"ghsa":5.5,"vendor":5.1},"ingestedAt":"2026-07-13T18:57:53.526Z","slug":"CVE-2026-42309","body":"## Overview\n\nPassing nested lists as coordinates to APIs that accept coordinates such as `ImagePath.Path`, `ImageDraw.ImageDraw.polygon` and `ImageDraw.ImageDraw.line` could cause a heap buffer overflow, as nested lists were recursively unpacked beyond the allocated buffer. Coordinate lists are now validated to contain exactly two numeric coordinates. This was introduced in Pillow 11.2.1.\n\n## Affected packages\n\n- `pillow >= 11.2.1, < 12.2.0`\n\n## Remediation\n\nUpgrade to a patched release:\n\n- `pillow 12.2.0`\n\n## Vendor advisories\n\n- **RHSA-2026:16008** · Red Hat · fixed in: Red Hat AI Inference Server 3.3 · released 2026-05-11 · [advisory](https://access.redhat.com/errata/RHSA-2026:16008)\n- **RHSA-2026:16030** · Red Hat · fixed in: Red Hat AI Inference Server 3.3 · released 2026-05-11 · [advisory](https://access.redhat.com/errata/RHSA-2026:16030)\n- **RHSA-2026:16009** · Red Hat · fixed in: Red Hat AI Inference Server 3.3 · released 2026-05-11 · [advisory](https://access.redhat.com/errata/RHSA-2026:16009)\n- **RHSA-2026:57387** · Red Hat · fixed in: Red Hat AI Inference Server 3.4 · released 2026-08-20 · [advisory](https://access.redhat.com/errata/RHSA-2026:57387)\n- **Red Hat VEX** · Moderate · affected: Exploit Intelligence, OpenShift Lightspeed, Pen Drive Powered by Red Hat Lightspeed, Red Hat AI Inference Server, Red Hat Ansible Automation Platform 2, Red Hat Enterprise Linux 7, … · no fix planned: Exploit Intelligence, OpenShift Lightspeed, Pen Drive Powered by Red Hat Lightspeed, Red Hat AI Inference Server, … · updated 2026-10-09 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-42309.json)","depth":"sunlit","depthScore":30,"depthScoreParts":{"impact":30.3,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[{"seq":225179,"id":"CVE-2026-42309","ts":1792442514069,"field":"cvss","old":"5.1","new":"5.5"},{"seq":218445,"id":"CVE-2026-42309","ts":1791533737666,"field":"cvss","old":"5.5","new":"5.1"}]}