high7.5
CVE-2026-42245
Net::IMAP implements Internet Message Access Protocol (IMAP) client functionality in Ruby.
Impact
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.
Affected packages
| Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|
| rubygems | net-imap | >= 0.6.0, <= 0.6.3 | 0.6.4 |
Affected products
| Vendor | Product | Affected versions |
|---|---|---|
| Ruby-Lang | Net\ | before 0.4.24 from 0.5.0 before 0.5.14 from 0.6.0 before 0.6.4 |
Weakness classification
References
- NVD record
- CVE.org record
- GitHub advisory
- https://github.com/advisories/GHSA-q2mw-fvj9-vvcw
- https://github.com/ruby/net-imap/security/advisories/GHSA-q2mw-fvj9-vvcw
- 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://nvd.nist.gov/vuln/detail/CVE-2026-42245
- https://github.com/rubysec/ruby-advisory-db/blob/master/gems/net-imap/CVE-2026-42245.yml