CVE-2026-42257 MEDIUM

CVE-2026-42257: net-imap: Command Injection via "raw" arguments to multiple commands

Vendor Ruby
Product net-imap
Weakness CWE-93 · CRLF injection
Published May 9, 2026
Last update May 13, 2026
View on NVD All CVEs

CVSS base score

5.8/10
Attack vector Local
Attack complexity Low
Privileges required None
User interaction —
Confidentiality —
Integrity —

CVSS vector

CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:P/VC:N/VI:H/VA:L/SC:N/SI:N/SA:N

What the vulnerability does

01Description

Net::IMAP implements Internet Message Access Protocol (IMAP) client functionality in Ruby. Prior to versions 0.4.24, 0.5.14, and 0.6.4, several Net::IMAP commands accept a raw string argument that is sent to the server without validation or escaping. If this string is derived from user-controlled input, it may contain contain CRLF sequences, which an attacker can use to inject arbitrary IMAP commands. This issue has been patched in versions 0.4.24, 0.5.14, and 0.6.4.

Key dates

02Disclosure timeline

May 9, 2026 CVE published
May 13, 2026 Record updated