CVE-2026-41313: pypdf · Possible long runtimes for wrong size values in incremental mode
Affects pypdfSource GCVE Database
Not known to be exploited · CVSS 4.8 Medium : upgrade to 6.10.2 when convenient.
Data as of 27 Oct 2026, 00:07 UTC
- Patch
- Available – fixed in 6.10.2
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 22 Apr 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: 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 26 Oct 2026.
What to do
Upgrade pypdf to 6.10.2.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| PyPIpypdf | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
Description
### Impact An attacker who uses this vulnerability can craft a PDF which leads to long runtimes. This requires loading a PDF with a large trailer `/Size` value in incremental mode. ### Patches This has been fixed in [pypdf==6.10.2](https://github.com/py-pdf/pypdf/releases/tag/6.10.2). ### Workarounds If you cannot upgrade yet, consider applying the changes from PR [#3735](https://github.com/py-pdf/pypdf/pull/3735).
References
- github.com/py-pdf/pypdf/security/advisories/GHSA-4pxv-j86v-mhcw (opens in a new tab)
- nvd.nist.gov/vuln/detail/CVE-2026-41313 (opens in a new tab)
- github.com/py-pdf/pypdf/pull/3735 (opens in a new tab)
- github.com/py-pdf/pypdf/commit/c50a0104cf083356f7c7f5d61410466a57f5c88a (opens in a new tab)
- github.com/py-pdf/pypdf (opens in a new tab)
- github.com/py-pdf/pypdf/releases/tag/6.10.2 (opens in a new tab)