Vulnerability in Netty
CVE-2026-59921
Netty is an asynchronous, event-driven network application framework. Prior to versions 4.1.136.Final and 4.2.16.Final, HttpPostRequestEncoder constructs multipart HTTP request bodies by directly concatenating user-supplied filenames and f…
Vulnerability class: CRLF Injection
CVSS v3 metric
CVSS v3 base score 5.7 (Medium). Vector: CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N.
Affected products
- Netty — versions >= 4.2.0.Final, < 4.2.16.Final, >=4.2.0.Final, < 4.2.16.Final, < 4.1.136.Final
Weakness classification (CWE)
References
- security-advisories@github.com (x_refsource_CONFIRM)
Frequently asked questions
- What is CVE-2026-59921?
- CVE-2026-59921 is a medium-severity vulnerability in Netty, classified under CRLF Injection. CVSS score: 5.7/10. Published 2026-07-28.
- How severe is CVE-2026-59921?
- Medium severity. CVSS v3 base score is 5.7 out of 10.