CVE-2026-77220

Summary

PDFio before 1.6.5 contains a dangling pointer vulnerability in the dictionary string-formatting function that stores a pointer to a stack-local buffer in the document dictionary without copying the string value. In multi-threaded or pooled-request environments, attackers or concurrent users can trigger stack memory reuse across requests, causing cross-tenant document content corruption by silently overwriting one caller's dictionary string values with another caller's data.

Affected Software

VendorProductVersion RangeStatus
michaelrsweetpdfio0 < 1.6.5affected

Weaknesses

  • CWE-825: Expired Pointer Dereference

References