Medium severity · published Oct 21, 2026
CVE-2026-113794
pypdf: Possible infinite loop when hitting EOF in standard xref table
6.0
CVSS
0.5%
EPSS
No
On KEV
Description
pypdf is a free and open-source pure-python PDF library. Prior to 6.20.0, an attacker can craft an incomplete PDF that ends inside a standard cross-reference table, causing pypdf to mishandle the unexpected end of file and enter an infinite loop. This issue is fixed in version 6.20.0.
Exploitation
Is it being used?
Exploit prediction (EPSS)0.5% · higher than 40% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
PY
pypdf · py-pdf
< 6.20.0 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-113794
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-113794
github.com
https://github.com/py-pdf/pypdf/commit/37e1cd681744bac38b159f7e1c614eee8d639c58
github.com
https://github.com/py-pdf/pypdf/issues/4169
github.com
https://github.com/py-pdf/pypdf/pull/4170
github.com
https://github.com/py-pdf/pypdf/releases/tag/6.20.0
github.com
https://github.com/py-pdf/pypdf/security/advisories/GHSA-39mj-jf6j-2qj3
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