CVE-2026-49460: pypdf: Inefficient decoding of FlateDecode PNG predictor streams

June 16, 2026

An attacker who uses this vulnerability can craft a PDF which leads to long runtimes. This requires accessing a stream which uses the /FlateDecode filter with a PNG predictor.

References

github.com/advisories/GHSA-5hgr-hg42-57jg
github.com/py-pdf/pypdf/pull/3806
github.com/py-pdf/pypdf/releases/tag/6.12.2
github.com/py-pdf/pypdf/security/advisories/GHSA-5hgr-hg42-57jg
nvd.nist.gov/vuln/detail/CVE-2026-49460

Code Behaviors & Features

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