CVE-2026-42245: net-imap has quadratic complexity when reading response literals
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.
References
- github.com/advisories/GHSA-q2mw-fvj9-vvcw
- github.com/ruby/net-imap
- github.com/ruby/net-imap/commit/6091f7d6b1f3514cafbfe39c76f2b5d73de3ca96
- github.com/ruby/net-imap/commit/88d95231fc8afef11c1f074453f7d75b68c9dfda
- github.com/ruby/net-imap/commit/de685f91a4a4cc75eb80da898c2bf8af08d34819
- github.com/ruby/net-imap/releases/tag/v0.4.24
- github.com/ruby/net-imap/releases/tag/v0.5.14
- github.com/ruby/net-imap/releases/tag/v0.6.4
- github.com/ruby/net-imap/security/advisories/GHSA-q2mw-fvj9-vvcw
- nvd.nist.gov/vuln/detail/CVE-2026-42245
Code Behaviors & Features
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