CVE-2026-42257
net-imap vulnerable to command Injection via "raw" arguments to multiple commands
9.8
CRITICAL
CVSS 3.1
EPSS 0.02%
Description
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.
How to fix CVE-2026-42257
To remediate CVE-2026-42257, upgrade the affected package to a fixed version below.
- —no fix listed
- —no fix listed
- —no fix listed
- —upgrade to 0.6.4 or later
Is CVE-2026-42257 being exploited?
Low — EPSS is 0.0%, meaning exploitation activity has not been observed at scale.
Affected packages (4)
- from 0
- from 0
- from 0
- >= 0.6.0, < 0.6.4
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 4.0 | — | 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 |
| osv | CVSS 3.1 | CRITICAL9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |