Fluid Attacks Database

Description

pypdf: Inefficient handling of non-whitespace inputs in read_until_whitespace

Impact

An attacker who uses this vulnerability can craft a PDF which leads to long runtimes. This requires a call to read_until_whitespace with an input which does not have whitespace for a long time.

Patches

This has been fixed in pypdf==6.15.0.

Workarounds

If you cannot upgrade yet, consider applying the changes from PR #3947.

Mitigation

Update Impact

Minimal update. May introduce new vulnerabilities or breaking changes.

Ecosystem	Component	Affected version	Patched versions
debian 14	pypdf	=5.4.0-1 \|\| =6.9.0-1 \|\| =6.9.2-1 \|\| =6.9.2-2 \|\| >=0 <6.19.0-1	6.19.0-1
debian 13	pypdf	=5.4.0-1 \|\| =6.19.0-1 \|\| =6.9.0-1 \|\| =6.9.2-1 \|\| =6.9.2-2	-
debian 12	pypdf	=3.17.4-1 \|\| =3.4.1-1 \|\| =3.4.1-1+deb12u1 \|\| =4.0.0-1 \|\| =4.0.0-1~exp1 \|\| =4.0.1-1 \|\| =4.0.2-1 \|\| =4.1.0-1 \|\| =4.2.0-1 \|\| =4.3.1-1 \|\| =5.4.0-1 \|\| =6.19.0-1 \|\| =6.9.0-1 \|\| =6.9.2-1 \|\| =6.9.2-2	-
debian 12	pypdf2	=2.12.1-3 \|\| =2.12.1-3+deb12u1 \|\| =2.12.1-4	-
pypi	pypdf	>=0 <6.15.0	6.15.0

Aliases

1. CVE-2026-823982. NVD-2026-823983. OSV-DEBIAN-2026-823984. OSV-2026-823985. GHSA-fc8x-2rww-xw9m6. GCVE-2026-823987. SECURITY-TRACKER-CVE-2026-82398

References

1. https://github.com/py-pdf/pypdf/security/advisories/GHSA-fc8x-2rww-xw9m2. https://github.com/py-pdf/pypdf/pull/39473. https://github.com/py-pdf/pypdf/commit/4959848e057e37c218dccad7465259210923faaa4. https://github.com/py-pdf/pypdf/releases/tag/6.15.0

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