High severity · published Oct 29, 2026
CVE-2026-119206
pypdf: Possible long runtimes when retrieving page labels
New
7.1
CVSS
–
EPSS
No
On KEV
Description
pypdf is a free and open-source pure-python PDF library. Prior to 6.21.3, pypdf can take excessive time to retrieve page labels from a crafted PDF containing a flat page-label number tree with many ranges. The page_labels property resolves each page independently and repeatedly scans the same /Nums array from the beginning, causing work to grow with both the page count and the number of label ranges. This issue is fixed in version 6.21.3.
Exploitation
Is it being used?
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
PY
pypdf · py-pdf
< 6.21.3 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-119206
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-119206
x_refsource_CONFIRM
https://github.com/py-pdf/pypdf/security/advisories/GHSA-42gh-23hr-vphw
x_refsource_MISC
https://github.com/py-pdf/pypdf/pull/4251
x_refsource_MISC
https://github.com/py-pdf/pypdf/commit/b891fef37000cd86baa6e9848a3387d080b3b03e
x_refsource_MISC
https://github.com/py-pdf/pypdf/releases/tag/6.21.3
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