Answer in brief
CVE-2026-42309 records a Medium severity (CVSS 5.5) vulnerability in Pillow has a heap buffer overflow with nested list coordinates. The current sources do not mark it as known exploited. The current feed maps pillow (pip). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 5.5. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps pillow (pip). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| pillowpip | >=11.2.1,<12.2.0 | 12.2.0 |
Published upstream
May 4, 2026
Evidence: source:ghsa:source_dates:source-dates:recordSource modified
Oct 19, 2026
Evidence: source:ghsa:source_dates:source-dates:recordFirst seen by HOL
Oct 19, 2026
Passing 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.
Quoted source text, attributed separately from HOL analysis.