All vulnerabilities
CVE-2026-102998GHSA-php9-fj8v-98fjPYSEC-2026-4157

pypdf: Possible long runtimes when generating appearance streams

py-pdf pypdfpipLibraries & packages
Open in ThreatlineRecord JSON
CVSS
8.7High
ExploitationNo known exploitationNot in CISA KEV, which does not prove it is unexploitedCISA KEV
Exploit odds (EPSS)0.34%Chance of exploitation activity in the next 30 days, higher than 26% of CVEs. Scored 23 Oct 2026FIRST EPSS
Fixed in6.19.0Fixed versionGitHub
Published30 Sep 2026Updated 1 Oct 2026CVE List

What fixes it

  • 6.19.0pypdf, pipGitHub
  • 6.19.0pypdf, PyPIOSVpip install "pypdf>=6.19.0"

A fixed version on one release line is not the upgrade target for every line. Check your exact version and any vendor backports.

Description

Impact

An attacker who uses this vulnerability can craft a PDF which leads to long runtimes. This requires updating form field values with flattening enabled, which triggers appearance stream generation.

Patches

This has been fixed in pypdf==6.19.0.

Workarounds

If you cannot upgrade yet, consider applying the changes from PR #4087.

Text from GitHub Advisory Database

Affected versions 53

  • pypdf, pip< 6.19.0GitHub
  • pypdfaffected: < 6.19.0CVE List
  • pypdf, PyPIfrom first release, fixed in 6.19.0OSV
  • pypdf, PyPI1.0OSV
  • pypdf, PyPI1.1OSV
  • pypdf, PyPI1.10OSV
  • pypdf, PyPI1.11OSV
  • pypdf, PyPI1.12OSV
  • pypdf, PyPI1.13OSV
  • pypdf, PyPI1.2OSV
  • pypdf, PyPI1.3OSV
  • pypdf, PyPI1.4OSV
  • pypdf, PyPI1.5OSV
  • pypdf, PyPI1.6OSV
  • pypdf, PyPI1.7OSV
  • pypdf, PyPI1.8OSV
  • pypdf, PyPI1.9OSV
  • pypdf, PyPI3.1.0OSV
  • pypdf, PyPI3.10.0OSV
  • pypdf, PyPI3.11.0OSV
  • pypdf, PyPI3.11.1OSV
  • pypdf, PyPI3.12.0OSV
  • pypdf, PyPI3.12.1OSV
  • pypdf, PyPI3.12.2OSV
  • pypdf, PyPI3.13.0OSV
  • pypdf, PyPI3.14.0OSV
  • pypdf, PyPI3.15.0OSV
  • pypdf, PyPI3.15.1OSV
  • pypdf, PyPI3.15.2OSV
  • pypdf, PyPI3.15.3OSV
  • pypdf, PyPI3.15.4OSV
  • pypdf, PyPI3.15.5OSV
  • pypdf, PyPI3.16.0OSV
  • pypdf, PyPI3.16.1OSV
  • pypdf, PyPI3.16.2OSV
  • pypdf, PyPI3.16.3OSV
  • pypdf, PyPI3.16.4OSV
  • pypdf, PyPI3.17.0OSV
  • pypdf, PyPI3.17.1OSV
  • pypdf, PyPI3.17.2OSV
  • pypdf, PyPI3.17.3OSV
  • pypdf, PyPI3.17.4OSV
  • pypdf, PyPI3.2.0OSV
  • pypdf, PyPI3.2.1OSV
  • pypdf, PyPI3.3.0OSV
  • pypdf, PyPI3.4.0OSV
  • pypdf, PyPI3.4.1OSV
  • pypdf, PyPI3.5.0OSV
  • pypdf, PyPI3.5.1OSV
  • pypdf, PyPI3.5.2OSV
  • pypdf, PyPI3.6.0OSV
  • pypdf, PyPI3.7.0OSV
  • pypdf, PyPI3.7.1OSV

References 6