CVE-2026-120251
imagecodecs 2026.3.6 through 2026.10.10 Infinite Loop via ccittfax4_decode()
- State
- Published
- Severity
- 6.8 Medium
- Published
- Nov 1, 2026
- Updated
- Nov 1, 2026
- Reserved
- Oct 31, 2026
Description
imagecodecs 2026.3.6 through 2026.10.10 contains an infinite loop vulnerability in ccitt_fax4_decode_size() that allows attackers to hang the calling process by supplying a crafted CCITT Group 4 stream. Attackers can provide an 8-byte G4 stream lacking EOFB to ccittfax4_decode() or the numcodecs Ccittfax4 codec, consuming full CPU until the process is killed.
Scores
| CVSS | Score | Vector | Source |
|---|---|---|---|
| 4.0 | 6.8 Medium | CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N | VulnCheck |
| 3.1 | 5.5 Medium | CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H | VulnCheck |
Weaknesses
- CWE-835 Loop with Unreachable Exit Condition ('Infinite Loop')
Affected Products
| Product | Versions |
|---|---|
imagecodecscgohlke |
|
References
- GitHub Issue #158issue-tracking
- https://github.com/cgohlke/imagecodecs/blob/v2026.10.10/3rdparty/ccitt/ccitt.c#L1449technical-description
- https://github.com/cgohlke/imagecodecsproduct
- VulnCheck Advisory: imagecodecs 2026.3.6 through 2026.10.10 Infinite Loop via ccittfax4_decode()third-party-advisory
Every record here comes from the CVE Program’s CVE List. © 1999–2026 The MITRE Corporation. CVE is a registered trademark of The MITRE Corporation. The records are reproduced under the CVE Program terms of use.