CVE-2026-42257

MEDIUM EPSS 34.4%
Published May 9, 20261mo ago · Modified Jun 17, 20262w ago
5.8 CVSS 4.0
Medium
Find Similar
Published May 9, 2026 1mo ago
Last Modified Jun 17, 2026 2w ago

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.

CVSS Details

Base Score
5.8
Exploitability
—
Impact
—
Vector string
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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Attack Vector Local
Attack Complexity Low
Privileges Required None
User Interaction P
Scope X

Threat Intelligence

EPSS Exploit Probability
34.4% percentile
Exploit & Patch Status
No Known Exploit
No Patch Available

Weaknesses 2

CWE-77 Command Injection Injection
CWE-93

Affected Products 3

VendorProductVersionRange
ruby-langnet\\ <0.4.24
ruby-langnet\\≥0.5.0  –  <0.5.14
ruby-langnet\\≥0.6.0  –  <0.6.4

References 4

  • github.com https://github.com/ruby/net-imap/releases/tag/v0.4.24
    Release Notes
  • github.com https://github.com/ruby/net-imap/releases/tag/v0.5.14
    Release Notes
  • github.com https://github.com/ruby/net-imap/releases/tag/v0.6.4
    Release Notes
  • github.com https://github.com/ruby/net-imap/security/advisories/GHSA-hm49-wcqc-g2xg
    MitigationVendor Advisory

Remediation

No remediation data recorded yet

Check vendor advisories and the NVD entry for patch availability.