Medium severity · published Apr 22, 2026
CVE-2026-41168
pypdf has possible long runtimes for wrong size values in cross-reference and object streams
5.3
CVSS
0.3%
EPSS
No
On KEV
Description
pypdf is a free and open-source pure-python PDF library. An attacker who uses a vulnerability present in versions prior to 6.10.1 can craft a PDF which leads to long runtimes. This requires cross-reference streams with wrong large `/Size` values or object streams with wrong large `/N` values. This has been fixed in pypdf 6.10.1. As a workaround, one may apply 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:L
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
Low
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 22% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
PY
pypdf · py-pdf
< 6.10.1 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-41168
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-41168
Patch
https://github.com/py-pdf/pypdf/commit/62338e9d36419cf193ccec7331784f45df1d70b3
Issue Tracking
https://github.com/py-pdf/pypdf/pull/3733
Product
https://github.com/py-pdf/pypdf/releases/tag/6.10.1
Mitigation
https://github.com/py-pdf/pypdf/security/advisories/GHSA-jj6c-8h6c-hppx
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