High severity · published Oct 29, 2026
CVE-2026-119207
pypdf: Possible large memory usage for exceptions in strict mode
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 consume excessive memory when strict mode loads a crafted invalid PDF dictionary. Nested parsing failures add repeated exception text to newly raised errors, allowing a small malformed dictionary to amplify into very large error messages. 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-2026-119207
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-119207
x_refsource_CONFIRM
https://github.com/py-pdf/pypdf/security/advisories/GHSA-4vqv-7265-gm2w
x_refsource_MISC
https://github.com/py-pdf/pypdf/pull/4265
x_refsource_MISC
https://github.com/py-pdf/pypdf/commit/64270258c0eced720f7960aecf8cef31afd39f8d
x_refsource_MISC
https://github.com/py-pdf/pypdf/releases/tag/6.21.3
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