CVE-2026-84311
pypdf: Possible long runtimes/large memory usage when extracting XForm objects
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.
No summary for this CVE yet.
Weaknesses
Affected Products
py-pdf
package-ecosystemaka pypdf2, pypdf
pypdfOn-prem
OSS Libraries / pypiExploitability
No known exploits, KEV entries, or remediation guidance available for this vulnerability yet.
Attack Graph
Products CVE Techniques Tactics
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MITRE ATT&CK
1 technique Impact
References
https://github.com/py-pdf/pypdf/commit/d91ab705fd81ed1a9cec175c6958600dea1a4942
github.com
https://github.com/py-pdf/pypdf/pull/3966
github.com
https://github.com/py-pdf/pypdf/releases/tag/6.16.1
github.com
and 1 more references View all →
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