Vulnerability · Published Oct 21, 2026 · Assigned by GitHub_M
CVE-2026-113794pypdf: Possible infinite loop when hitting EOF in standard xref table
Medium 6.0
In plain English
A medium-severity infinite loop in pypdf from py-pdf. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 29% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Severity (CVSS 4.0)6.0Medium
Exploit odds (30 days)0.4%top 70.7% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known
Official description
pypdf is a free and open-source pure-python PDF library. Prior to 6.20.0, an attacker can craft an incomplete PDF that ends inside a standard cross-reference table, causing pypdf to mishandle the unexpected end of file and enter an infinite loop. This issue is fixed in version 6.20.0.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | pypdf | no fix listed | DEBIAN-CVE-2026-113794 |
| Debian:13 | pypdf | no fix listed | DEBIAN-CVE-2026-113794 |
| Debian:14 | pypdf | 6.21.0-1 | DEBIAN-CVE-2026-113794 |
| Debian:12 | pypdf2 | no fix listed | DEBIAN-CVE-2026-113794 |
| PyPI | pypdf | 6.20.0 | GHSA-39mj-jf6j-2qj3 |
| Ubuntu:24.04:LTS | pypdf | no fix listed | UBUNTU-CVE-2026-113794 |
| Ubuntu:26.04:LTS | pypdf | no fix listed | UBUNTU-CVE-2026-113794 |
| Ubuntu:26.10 | pypdf | no fix listed | UBUNTU-CVE-2026-113794 |
| Ubuntu:22.04:LTS | pypdf2 | no fix listed | UBUNTU-CVE-2026-113794 |
| Ubuntu:24.04:LTS | pypdf2 | no fix listed | UBUNTU-CVE-2026-113794 |
Affected products (as reported)
Weakness: CWE-835 · Vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
References
- https://github.com/py-pdf/pypdf/security/advisories/GHSA-39mj-jf6j-2qj3 x_refsource_CONFIRM
- https://github.com/py-pdf/pypdf/issues/4169 x_refsource_MISC
- https://github.com/py-pdf/pypdf/pull/4170 x_refsource_MISC
- https://github.com/py-pdf/pypdf/commit/37e1cd681744bac38b159f7e1c614eee8d639c58 x_refsource_MISC
- https://github.com/py-pdf/pypdf/releases/tag/6.20.0 x_refsource_MISC