CVE-2026-41312

pypdf: Manipulated FlateDecode predictor parameters can exhaust RAM

State
Published
Severity
4.8 Medium
Published
Apr 22, 2026
Updated
Apr 23, 2026
Reserved
Apr 20, 2026

Read the record on cve.org

Description

pypdf is a free and open-source pure-python PDF library. An attacker who uses a vulnerability present in versions prior to 6.10.2 can craft a PDF which leads to the RAM being exhausted. This requires accessing a stream compressed using `/FlateDecode` with a `/Predictor` unequal 1 and large predictor parameters. This has been fixed in pypdf 6.10.2. As a workaround, one may apply the changes from the patch manually.

Scores

CVSSScoreVectorSource
4.04.8 MediumCVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:L/SC:N/SI:N/SA:NGitHub_M

Weaknesses

  • CWE-789 Memory Allocation with Excessive Size Value

Affected Products

ProductVersions
pypdfpy-pdf
  • < 6.10.2Affected

References

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