CVE-2026-42257
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.
Published:May 9, 2026
Last Modified:May 18, 2026
EPS:May 9, 2026
EPSS Score:0.00028
CVSS Score:9.8
Affected Products
Vendor
Product
Action
Vendor
Ruby-lang
Product
Net::imap
Ruby-lang
Net::imap
Vendor
Ruby-lang
Product
Net\
Ruby-lang
Net\
Exploits
No exploit reference
Common Weakness Enumeration
Common Attack Pattern Enumeration and Classification (CAPEC)
Related CVEs
Common Vulnerability Scoring System
Attack Vector
Network
Adjacent
Local
Physical
Privileges Required
None
Low
High
User Interaction
None
Required
Scope
Unchanged
Changed
Confidentiality
None
Low
High
Integrity
None
Low
High
Availability
None
Low
High
