CVE-2026-42257

Publication date 9 May 2026

Last updated 19 June 2026

Ubuntu priority

Medium

Why this priority?

Cvss 3 Severity Score

9.8 · Critical

Score breakdown

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, several Net::IMAP commands accept a raw string argument that is sent to the server without validation or escaping. If this string is derived from user-controlled input, it may contain contain CRLF sequences, which an attacker can use to inject arbitrary IMAP commands. This issue has been patched in versions 0.4.24, 0.5.14, and 0.6.4.

Status

Package Ubuntu Release Status
ruby2.3 26.04 LTS resolute Not in release
25.10 questing Not in release
24.04 LTS noble Not in release
22.04 LTS jammy Not in release
16.04 LTS xenial
Fixed 2.3.1-2~ubuntu16.04.16+esm14
ruby2.5 26.04 LTS resolute Not in release
25.10 questing Not in release
24.04 LTS noble Not in release
22.04 LTS jammy Not in release
18.04 LTS bionic
Fixed 2.5.1-1ubuntu1.16+esm8
ruby2.7 26.04 LTS resolute Not in release
25.10 questing Not in release
24.04 LTS noble Not in release
22.04 LTS jammy Not in release
20.04 LTS focal
Vulnerable
ruby3.0 26.04 LTS resolute Not in release
25.10 questing Not in release
24.04 LTS noble Not in release
22.04 LTS jammy
Vulnerable
ruby3.2 26.04 LTS resolute Not in release
25.10 questing Not in release
24.04 LTS noble
Vulnerable
22.04 LTS jammy Not in release
ruby3.3 26.04 LTS resolute
Vulnerable
25.10 questing Ignored end of standard support
24.04 LTS noble Not in release
22.04 LTS jammy Not in release
jruby 26.04 LTS resolute
Vulnerable
25.10 questing Ignored end of standard support
24.04 LTS noble
Vulnerable
22.04 LTS jammy Not in release
20.04 LTS focal
Vulnerable
18.04 LTS bionic
Vulnerable
16.04 LTS xenial Ignored end of ESM support, was needs-triage
14.04 LTS trusty
Vulnerable

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Severity score breakdown

CVSS version:

Base score 5.8 · Medium

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

Base score 9.8 · Critical

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

References

Related Ubuntu Security Notices (USN)

Other references

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