Vulnerability Description
Net::IMAP implements Internet Message Access Protocol (IMAP) client functionality in Ruby. From versions 0.4.0 to before 0.4.24, 0.5.0 to before 0.5.14, and 0.6.0 to before 0.6.4, 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. This issue has been patched in versions 0.4.24, 0.5.14, and 0.6.4.
CVSS Score
MEDIUM
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Ruby-Lang | Net\ | >= 0.4.0, < 0.4.24, \ |
Related Weaknesses (CWE)
References
- https://github.com/ruby/net-imap/commit/158d0b505074397cdb5ceb58935e42dd2bcfa612Patch
- https://github.com/ruby/net-imap/commit/808001bc45c06f7297a7e96d341279e041a7f7f4Patch
- https://github.com/ruby/net-imap/commit/99f59eab6064955a23debd95410263ad144df758Patch
- https://github.com/ruby/net-imap/releases/tag/v0.4.24Release Notes
- https://github.com/ruby/net-imap/releases/tag/v0.5.14Release Notes
- https://github.com/ruby/net-imap/releases/tag/v0.6.4Release Notes
- https://github.com/ruby/net-imap/security/advisories/GHSA-87pf-fpwv-p7m7MitigationVendor Advisory
FAQ
What is CVE-2026-42256?
CVE-2026-42256 is a vulnerability with a CVSS score of 6.5 (MEDIUM). Net::IMAP implements Internet Message Access Protocol (IMAP) client functionality in Ruby. From versions 0.4.0 to before 0.4.24, 0.5.0 to before 0.5.14, and 0.6.0 to before 0.6.4, when authenticating ...
How severe is CVE-2026-42256?
CVE-2026-42256 has been rated MEDIUM with a CVSS base score of 6.5/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-42256?
Check the references section above for vendor advisories and patch information. Affected products include: Ruby-Lang Net\.