CVE-2026-42256: net-imap vulnerable to denial of service via high iteration count for `SCRAM-*` authentication
(updated )
When authenticating a connection with SCRAM-SHA1 or SCRAM-SHA256, a hostile server can perform a computational denial-of-service attack on the client process by sending a big iteration count value.
References
- github.com/advisories/GHSA-87pf-fpwv-p7m7
- github.com/ruby/net-imap/commit/158d0b505074397cdb5ceb58935e42dd2bcfa612
- github.com/ruby/net-imap/commit/808001bc45c06f7297a7e96d341279e041a7f7f4
- github.com/ruby/net-imap/commit/99f59eab6064955a23debd95410263ad144df758
- 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-87pf-fpwv-p7m7
- github.com/rubysec/ruby-advisory-db/blob/master/gems/net-imap/CVE-2026-42256.yml
- nvd.nist.gov/vuln/detail/CVE-2026-42256
- www.rfc-editor.org/rfc/rfc7804.html
Code Behaviors & Features
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