Medium severity · published Oct 21, 2026
CVE-2026-113792
pypdf: Possible infinite loop in PdfWriter.find_outline_item
6.0
CVSS
0.5%
EPSS
No
On KEV
Description
pypdf is a free and open-source pure-python PDF library. Prior to 6.20.1, calling PdfWriter.find_outline_item on a crafted PDF with a cyclic outline hierarchy can enter an infinite loop and block the current process. This issue is fixed in version 6.20.1.
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
< 6.20.1 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-113792
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-113792
github.com
https://github.com/py-pdf/pypdf/commit/c9c35b4471c2eb5fe078094f6c816e69d4ed25a0
github.com
https://github.com/py-pdf/pypdf/pull/4188
github.com
https://github.com/py-pdf/pypdf/releases/tag/6.20.1
github.com
https://github.com/py-pdf/pypdf/security/advisories/GHSA-qfv9-64jg-mh7p
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