CRITICAL🇵🇱 Wersja polska

CVE-2026-21876

CVSS 9.3v3.1pub. 2026-01-08upd. 2026-04-09

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:N
  • Owasp Modsecurity Core Rule Set

    APP
    Owasp
    < 3.3.84.0.0 – 4.22.0 (bez)
🔵
CHECK WITH VENDOR
No clear patch data available. Check vendor references.
Tags
Firewall
CWE
References

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