Resource exhaustion in Py-Pdf Pypdf

CVE-2026-119207

pypdf is a free and open-source pure-python PDF library. Prior to 6.21.3, pypdf can consume excessive memory when strict mode loads a crafted invalid PDF dictionary. Nested parsing failures add repeated exception text to newly raised errors, allowing a small malformed dictionary to amplify into very large error messages. This issue is fixed in version 6.21.3.

Vulnerability class: DoS (Denial of Service)

Published .

EPSS exploit prediction

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Affected products

Weakness classification (CWE)

References