Vulnerability Details CVE-2026-42245
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, Net::IMAP::ResponseReader has quadratic time complexity when reading large responses containing many string literals. A hostile server can send responses which are crafted to exhaust the client's CPU for a denial of service attack. This issue has been patched in versions 0.4.24, 0.5.14, and 0.6.4.
Exploit prediction scoring system (EPSS) score
EPSS Score 0.001
EPSS Ranking 24.7%
CVSS Severity
CVSS v3 Score 7.5
References
- https://github.com/ruby/net-imap/commit/6091f7d6b1f3514cafbfe39c76f2b5d73de3ca96
- https://github.com/ruby/net-imap/commit/88d95231fc8afef11c1f074453f7d75b68c9dfda
- https://github.com/ruby/net-imap/commit/de685f91a4a4cc75eb80da898c2bf8af08d34819
- https://github.com/ruby/net-imap/releases/tag/v0.4.24
- https://github.com/ruby/net-imap/releases/tag/v0.5.14
- https://github.com/ruby/net-imap/releases/tag/v0.6.4
- https://github.com/ruby/net-imap/security/advisories/GHSA-q2mw-fvj9-vvcw