Summary
pypdf: Possible long runtimes/large memory usage when parsing indirect objects
Advisory details
Impact
An attacker who uses this vulnerability can craft a PDF which leads to long runtimes. This requires reading a PDF document with long indirect object headers, not terminated by whitespace.
Patches
This has been fixed in pypdf==6.18.0.
Workarounds
If you cannot upgrade yet, consider applying the changes from PR #4055.
References
- https://github.com/advisories/GHSA-5jq2-8x83-x246
- https://github.com/py-pdf/pypdf/security/advisories/GHSA-5jq2-8x83-x246
- https://nvd.nist.gov/vuln/detail/CVE-2026-102994
- https://github.com/py-pdf/pypdf/pull/4055
- https://github.com/py-pdf/pypdf/commit/82501d2993c6387833c4949d205caeb188f8bb9e
- https://github.com/py-pdf/pypdf/releases/tag/6.18.0
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