Connect your agent
AdvisoriesCriticalCheck your lockfilePluginHow it worksPricing Connect your agent

Advisory record · GHSA-23w6-3w8w-8484

pypdf: Possible long runtimes/large memory usage when retrieving outlines

CVSS 4.8 MediumEPSS 0.0014 · 2nd percentile

Published by the GitHub Advisory Database at 1 Sept 2026, 21:28 UTC. agentprime has not analysed this yet, so whether it affects any app is not known.

PackageEcosystemAffectedFixed in
pypdfPyPI<6.16.16.16.1
Identifiers
GHSA-23w6-3w8w-8484 · CVE-2026-84310 · PYSEC-2026-3910
Weakness (CWE)
CWE-405 · CWE-834
Tags
Published
1 Sept 2026
Updated
10 Sept 2026

Machine-written summary

Summary written by Claude Haiku from the source advisory. Not reviewed by a person.

pypdf versions before 6.16.1 are vulnerable to long runtimes and high memory use when retrieving a PDF's outlines. An attacker who supplies a crafted PDF can trigger this by getting the program to read the document's outlines, which have many entries or deeply nested re-used paths. Upgrade to pypdf 6.16.1 or later. The source does not describe a workaround the reader can apply without patching.

Written 1 Nov 2026.

Not analysed yet

We haven’t published our analysis of this Advisory yet. Once a person has reviewed it, this page will say what’s vulnerable, what has to be true for your app to be affected, and how to check.

Severity and exploitation

ScoreRatingCVSSVectorSource
4.8 Medium 4.0 CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N CNA (GitHub_M)
  • CISA KEV Not listed.
  • EPSS 0.0014, the 2nd percentile, on 5 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.

Timeline

  1. 1 Sept 2026, 21:18 UTC Confirmed by NVD
  2. 31 Oct 2026, 14:10 UTC First seen by agentprime
  3. 31 Oct 2026, 14:10 UTC Confirmed by OSV

Sources

Facts on this page come from the GitHub Advisory Database (CC-BY 4.0), OSV and the other sources listed, as published. We don’t reproduce full advisory descriptions, which can contain exploit code.