CVE-2026-77220:
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.
CVE-2026-77220:
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.
CVE-2023-28428:
PDFio is a C library for reading and writing PDF files. In versions 1.1.0 and prior, a denial of service vulnerability exists in the pdfio parser. Crafted pdf files can cause the program to run at 100% utilization and never terminate. This is different from CVE-2023-24808. A patch for this issue is available in version 1.1.1.
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