Vulnerability in pypdf (CVE-2026-59938)
Summary
Vulnerability in pypdf (CVE-2026-59938). Risk of unauthorized operations or information disclosure. Mitigation: upgrade to 6.14.0 or later.
Original description
The description as published by the source.
Impact
An attacker who uses this vulnerability can craft a PDF which leads to large memory usage. This requires loading images where the declared size values are much too large compared to the actual data.
Patches
This has been fixed in pypdf==6.14.0.
Workarounds
If you cannot upgrade yet, consider applying the changes from PR #3888.
Source: NIST National Vulnerability Database NVD GitHub Advisory
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as CVE-2026-59938 has been found in pypdf.
Risk of unauthorized operations or information disclosure. CVSS score: 5.3/10.
What to do: upgrade pypdf to 6.14.0 or later.
If unsure, ask your IT team or search "pypdf CVE-2026-59938" on the vendor's site.
CVE-2026-59938 (pypdf) — CWE-789 / CVSS v3 5.3
Attack vector: remote (network-reachable) / unauthenticated / no user interaction
Patched: 6.14.0 — apply immediately
Workaround: If you cannot upgrade yet, consider applying the changes from PR #3888.
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
A vulnerability (CWE-789) exists in pypdf.
Check the vendor advisory for the affected versions of pypdf.
Severity: Medium (CVSS 5.3/10). Risk of unauthorized operations or information disclosure.
Update to 6.14.0.
Workaround: If you cannot upgrade yet, consider applying the changes from PR #3888.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Run grep -r 'pypdf' . against your dependency files (package-lock.json, requirements.txt, go.sum) to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
-
1Identify exposure identify
grep -r 'pypdf' . | grep -v node_modulesリポジトリと本番環境の依存ファイル (package-lock.json / requirements.txt / go.sum / Gemfile.lock 等) で
pypdfを grep し、稼働しているサービス・バージョンを把握する。 -
2Apply temporary workaround mitigate
If you cannot upgrade yet, consider applying the changes from PR [#3888](https://github.com/py-pdf/pypdf/pull/3888).パッチが適用されるまでの応急処置として、If you cannot upgrade yet, consider applying the changes from PR #3888. を実施。回避策の副作用 (機能低下) を確認した上で。
-
3Apply patch patch
Upgrade pypdf to 6.14.0ステージング環境で 6.14.0 に上げて回帰テスト → 本番反映。回帰テストはアプリの主要ハッピーパスを含めること。
-
4Post-deployment verification verify
Confirm patched version is live in productionパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。
Affected packages
Fix status by distribution
Fixed packages published by each distribution for this CVE
- Ubuntu UBUNTU-CVE-2026-59938 pypdf2
References
- advisory nvd.nist.gov
- advisory github.com
- package github.com
- package pypi.org
- web github.com
- web github.com
- web github.com
- web github.com