CVE-2026-33699 — Infinite Loop in Pypdf

CWE-835 — Infinite LoopCWE-606 — Unchecked Input for Loop Condition7 documents6 sources
Severity
4.6MEDIUMNVD
EPSS
0.0%
top 96.48%
CISA KEV
Not in KEV
Exploit
No known exploits
Affected products
4
Py-pdf PypdfPypdf Project PypdfDebian Pypdf+1 more
Timeline
PublishedMar 27

Description

pypdf is a free and open-source pure-python PDF library. Versions prior to 6.9.2 have a vulnerability in which an attacker can craft a PDF which leads to an infinite loop. This requires reading a file in non-strict mode. This has been fixed in pypdf 6.9.2. If users cannot upgrade yet, consider applying the changes from the patch manually.

CVSS vector

CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

Affected Packages6 packages

▶CVEListV5py-pdf/pypdf< 6.9.2
▶debiandebian/pypdf< pypdf 6.9.2-1 (forky)
▶debiandebian/pypdf2< pypdf 6.9.2-1 (forky)
▶NVDpypdf_project/pypdf< 6.9.2
▶PyPIpypdf_project/pypdf< 6.9.2

Patches

Patch: github.com ↗Patch: github.com ↗

🔴Vulnerability Details

3
OSV
CVE-2026-33699: pypdf is a free and open-source pure-python PDF library↗2026-03-27
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OSV
pypdf: Possible infinite loop during recovery attempts in DictionaryObject.read_from_stream↗2026-03-25
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GHSA
pypdf: Possible infinite loop during recovery attempts in DictionaryObject.read_from_stream↗2026-03-25
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📋Vendor Advisories

2
Red Hat
pypdf: pypdf: Denial of Service via crafted PDF in non-strict mode↗2026-03-26
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Debian
CVE-2026-33699: pypdf - pypdf is a free and open-source pure-python PDF library. Versions prior to 6.9.2...↗2026
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🕵️Threat Intelligence

1
Wiz
CVE-2026-33699 Impact, Exploitability, and Mitigation Steps | Wiz↗
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