CVE-2026-27888

pypdf: Manipulated FlateDecode XFA streams can exhaust RAM

State
Published
Severity
6.6 Medium
Published
Feb 26, 2026
Updated
Jun 23, 2026
Reserved
Feb 24, 2026

Read the record on cve.org

Description

pypdf is a free and open-source pure-python PDF library. Prior to 6.7.3, an attacker who uses this vulnerability can craft a PDF which leads to the RAM being exhausted. This requires accessing the `xfa` property of a reader or writer and the corresponding stream being compressed using `/FlateDecode`. This has been fixed in pypdf 6.7.3. As a workaround, apply the patch manually.

Scores

CVSSScoreVectorSource
4.06.6 MediumCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:UGitHub_M

Weaknesses

  • CWE-400 Uncontrolled Resource Consumption

Affected Products

ProductVersions
pypdfpy-pdf
  • < 6.7.3Affected

References

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