CVE-2026-42257: medium-severity vulnerability in ruby net-imap
net-imap: Command Injection via "raw" arguments to multiple commands
Published · Updated
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13Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 5.8epss 0.4%
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.
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
Affected products
ruby · net-imapRelated CVEs — ruby net-imap
In the same product, most dangerous first.
CVE-2026-47240MEDIUMNet::IMAP: Command Injection via non-synchronizing literal in "raw" argumentEPSS 0.8%CVE-2026-42258MEDIUMnet-imap: Command Injection via unvalidated Symbol inputsEPSS 0.8%CVE-2025-25186MEDIUMNet::IMAP vulnerable to possible DoS by memory exhaustionEPSS 0.6%CVE-2025-43857MEDIUMnet-imap rubygem vulnerable to possible DoS by memory exhaustionEPSS 0.5%CVE-2026-42245LOWnet-imap: Quadratic complexity when reading response literalsEPSS 0.4%CVE-2026-47241LOWNet::IMAP: Denial of Service via incomplete raw argument validationEPSS 0.4%