CVE-2026-119203: py-pdf pypdf · Infinite Loop
Affects py-pdf pypdfSource CVE Database V5
Not known to be exploited · CVSS 7.1 High : upgrade to 6.21.4 soon.
Data as of 29 Oct 2026, 21:14 UTC
Thin evidence
One scorer or none| CNA (GitHub_M) | CVSS 4.0 | 7.1 |
|---|
- Patch
- Available – fixed in 6.21.4
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:NExploitation evidence
Disclosed: evidence found.
CVE published 29 Oct 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 29 Oct 2026.
What to do
Upgrade py-pdf pypdf to 6.21.4.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| py-pdfpypdf | Affected
| Fixed in
|
AI-suggested
Upgrade pypdf to version 6.21.4 or later, where this infinite loop vulnerability has been fixed. No other mitigation is required as the issue is resolved in the official patch.
Description
pypdf versions prior to 6.21.4 contain a vulnerability where opening a crafted incomplete PDF with a cross-reference table that reaches the end of the file without a trailer can cause an infinite loop. This occurs because the trailer search repeatedly rewinds to the same stream position without making progress, blocking the processing thread. The issue is fixed in version 6.21.4.