CVE-2026-84311: pypdf · Possible long runtimes/large memory usage when extracting XForm objects
Affects psutilsSource GCVE Database
Not known to be exploited · CVSS 4.8 Medium : upgrade to 3.3.16_2 when convenient.
Data as of 1 Nov 2026, 00:10 UTC
- Patch
- Available – fixed in 3.3.16_2
CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:L/SC:N/SI:N/SA:NExploitation evidence
Disclosed: evidence found.
CVE published 1 Sep 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 31 Oct 2026.
What to do
Upgrade psutils to 3.3.16_2.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Homebrewpsutilspkg:brew/psutilsOther threats | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
Upgrade pypdf to version 6.16.1 or later, where this vulnerability is fixed. If upgrading is not immediately possible, apply the changes from pull request #3966 as a temporary workaround.
Description
CVE-2026-84311 is a vulnerability in pypdf that allows crafted PDF files with many XForm objects to cause long runtimes and large memory consumption during text extraction. This can degrade performance but does not indicate code execution or data corruption. The issue is fixed in pypdf version 6.16.1.
References
- github.com/py-pdf/pypdf/security/advisories/GHSA-763m-79hh-57f2 (opens in a new tab)
- github.com/py-pdf/pypdf/pull/3966 (opens in a new tab)
- github.com/py-pdf/pypdf/commit/d91ab705fd81ed1a9cec175c6958600dea1a4942 (opens in a new tab)
- github.com/py-pdf/pypdf (opens in a new tab)
- github.com/py-pdf/pypdf/releases/tag/6.16.1 (opens in a new tab)