CVE-2026-42245

low

Description

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.

References

https://github.com/ruby/net-imap/security/advisories/GHSA-q2mw-fvj9-vvcw

https://github.com/ruby/net-imap/releases/tag/v0.6.4

https://github.com/ruby/net-imap/releases/tag/v0.5.14

https://github.com/ruby/net-imap/releases/tag/v0.4.24

https://github.com/ruby/net-imap/commit/de685f91a4a4cc75eb80da898c2bf8af08d34819

https://github.com/ruby/net-imap/commit/88d95231fc8afef11c1f074453f7d75b68c9dfda

https://github.com/ruby/net-imap/commit/6091f7d6b1f3514cafbfe39c76f2b5d73de3ca96

Details

Source: Mitre, NVD

Published: 2026-05-09

Updated: 2026-05-18

Risk Information

CVSS v2

Base Score: 7.8

Vector: CVSS2#AV:N/AC:L/Au:N/C:N/I:N/A:C

Severity: High

CVSS v3

Base Score: 7.5

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Severity: High

CVSS v4

Base Score: 2.3

Vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N

Severity: Low

EPSS

EPSS: 0.00062