Low severity · published Sep 1, 2026
CVE-2026-84311
pypdf: Possible long runtimes/large memory usage when extracting XForm objects
3.3
CVSS
0.1%
EPSS
No
On KEV
Description
pypdf is a free and open-source pure-python PDF library. Prior to 6.16.1, an attacker can craft a PDF that causes pypdf/_page.py PageObject._extract_text and PageObject.extract_xform_text to traverse a directed acyclic graph of reused form XObjects in which each form invokes a child multiple times, creating exponentially many traversal paths and causing long runtimes and large memory consumption. This issue is fixed in version 6.16.1.
CVSS vector
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L
Attack vector
Local
Complexity
Low
Privileges
None
User interaction
Required
Confidentiality
None
Integrity
None
Availability
Low
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.1% · higher than 3% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
PY
pypdf · py-pdf
< 6.16.1 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-84311
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-84311
Patch
https://github.com/py-pdf/pypdf/commit/d91ab705fd81ed1a9cec175c6958600dea1a4942
Patch
https://github.com/py-pdf/pypdf/pull/3966
Release Notes
https://github.com/py-pdf/pypdf/releases/tag/6.16.1
Patch
https://github.com/py-pdf/pypdf/security/advisories/GHSA-763m-79hh-57f2
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