CVE-2026-42246

CVE Details

Release Date:	2026-05-09
Impact:	Important	What is this?

Description

Net::IMAP implements Internet Message Access Protocol (IMAP) client functionality in Ruby. Prior to versions 0.3.10, 0.4.24, 0.5.14, and 0.6.4, a man-in-the-middle attacker can cause Net::IMAP#starttls to return "successfully", without starting TLS. This issue has been patched in versions 0.3.10, 0.4.24, 0.5.14, and 0.6.4.

See more information about CVE-2026-42246 from MITRE CVE dictionary and NIST NVD

NOTE: The following CVSS metrics and score provided are preliminary and subject to review.

CVSS v3 metrics

Base Score:	7.4
Vector String:	CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
Version:	3.1
Attack Vector:	Network
Attack Complexity:	High
Privileges Required:	None
User Interaction:	None
Scope:	Unchanged
Confidentiality Impact:	High
Integrity Impact:	High
Availability Impact:	None

Errata information

Platform	Errata	Release Date
Oracle Linux version 8 (ruby)	ELSA-2026-33514	2026-07-02
Oracle Linux version 8 (ruby)	ELSA-2026-33515	2026-07-01
Oracle Linux version 8 (rubygem-abrt)	ELSA-2026-33514	2026-07-02
Oracle Linux version 8 (rubygem-abrt)	ELSA-2026-33515	2026-07-01
Oracle Linux version 8 (rubygem-bson)	ELSA-2026-33514	2026-07-02
Oracle Linux version 8 (rubygem-bundler)	ELSA-2026-33514	2026-07-02
Oracle Linux version 8 (rubygem-mongo)	ELSA-2026-33514	2026-07-02
Oracle Linux version 8 (rubygem-mysql2)	ELSA-2026-33514	2026-07-02
Oracle Linux version 8 (rubygem-mysql2)	ELSA-2026-33515	2026-07-01
Oracle Linux version 8 (rubygem-pg)	ELSA-2026-33514	2026-07-02
Oracle Linux version 8 (rubygem-pg)	ELSA-2026-33515	2026-07-01
Oracle Linux version 9 (ruby)	ELSA-2026-33576	2026-07-02
Oracle Linux version 9 (rubygem-mysql2)	ELSA-2026-33576	2026-07-02
Oracle Linux version 9 (rubygem-pg)	ELSA-2026-33576	2026-07-02