High severity · published Mar 26, 2026
CVE-2026-33699
pypdf: Possible infinite loop during recovery attempts in DictionaryObject.read_from_stream
7.5
CVSS
0.5%
EPSS
No
On KEV
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:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.5% · higher than 41% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
PY
pypdf · py-pdf
< 6.9.2 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-33699
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-33699
Issue Tracking
https://github.com/py-pdf/pypdf/pull/3693
Product
https://github.com/py-pdf/pypdf/releases/tag/6.9.2
Patch
https://github.com/py-pdf/pypdf/security/advisories/GHSA-87mj-5ggw-8qc3
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