Pdfalyzer: pypdf has possible infinite loop when hitting EOF in standard xref table during trailer search
Affects pdfalyzerSource GCVE Database
Not known to be exploited · CVSS 7.1 High · fixed in 6.21.4 : patch pdfalyzer soon.
Data as of 31 Oct 2026, 15:55 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 30 Oct 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Homebrewpdfalyzerpkg:brew/pdfalyzerOther 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 to pypdf version 6.21.4 or later, which contains the official fix for this vulnerability. If upgrading immediately is not feasible, apply the changes from pull request #4289 in the pypdf repository as a temporary workaround.
Description
A vulnerability in pdfalyzer (pypdf) allows an attacker to craft a PDF file that causes an infinite loop when the parser encounters an incomplete file missing a trailer during the standard cross-reference table trailer search.
References
- github.com/py-pdf/pypdf/security/advisories/GHSA-5849-834g-hvw5 (opens in a new tab)
- nvd.nist.gov/vuln/detail/CVE-2026-119203 (opens in a new tab)
- github.com/py-pdf/pypdf/pull/4289 (opens in a new tab)
- github.com/py-pdf/pypdf/commit/06593f993789a4b573dd955730c1a7051128bb2a (opens in a new tab)
- github.com/py-pdf/pypdf (opens in a new tab)
- github.com/py-pdf/pypdf/releases/tag/6.21.4 (opens in a new tab)