CVE-2026-120251
imagecodecs 2026.3.6 through 2026.10.10 Infinite Loop via ccittfax4_decode()
CVSS Score
5.5
EPSS Score
0.0%
EPSS Percentile
0th
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.
| CWE | CWE-835 |
| Vendor | cgohlke |
| Product | imagecodecs |
| Published | Nov 1, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H Attack Vector
Local
Attack Complexity
Low
Privileges Required
None
User Interaction
Required
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High
Affected Versions
cgohlke / imagecodecs
2026.3.6 ≤ 2026.10.10
References
github.com: https://github.com/cgohlke/imagecodecs/issues/158 github.com: https://github.com/cgohlke/imagecodecs/blob/v2026.10.10/3rdparty/ccitt/ccitt.c#L1449 github.com: https://github.com/cgohlke/imagecodecs vulncheck.com: https://www.vulncheck.com/advisories/imagecodecs-2026.3.6-through-2026.10.10-infinite-loop-via-ccittfax4-decode
Credits
Dilanka Kaushal Hewage (r3vpwnx)