CVSS v3.1
9.3
EPSS
13.35%
Published
Jan 8, 2026
Modified
Apr 9, 2026
Public PoC / Exploit (2)
All weaponized →Links to public security research (Exploit-DB, Nuclei, Trickest, GitHub) for defensive use only.
Description
The OWASP core rule set (CRS) is a set of generic attack detection rules for use with compatible web application firewalls. Prior to versions 4.22.0 and 3.3.8, the current rule 922110 has a bug when processing multipart requests with multiple parts. When the first rule in a chain iterates over a collection (like `MULTIPART_PART_HEADERS`), the capture variables (`TX:0`, `TX:1`) get overwritten with each iteration. Only the last captured value is available to the chained rule, which means malicious charsets in earlier parts can be missed if a later part has a legitimate charset. Versions 4.22.0 and 3.3.8 patch the issue.
CVSS Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:L/A:NWeaknesses (CWE)
Affected Products (2)
References (6)