CVE-2026-42784

CVE Details

Release Date:	2026-09-16
Impact:	Important	What is this?

Description

A flaw was found in sequoia-openpgp. The library incorrectly infers key flags for older certificates when a key flags subpacket is missing, leading to a discrepancy in how key capabilities are viewed. This key flag confusion allows an attacker to bypass the back-signature check. Consequently, an attacker can illegitimately bind an arbitrary subkey to their own certificate and forge signatures, completely compromising cryptographic integrity.

See more information about CVE-2026-42784 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:L/PR:N/UI:R/S:C/C:N/I:H/A:N
Version:	3.1
Attack Vector:	Network
Attack Complexity:	Low
Privileges Required:	None
User Interaction:	Required
Scope:	Changed
Confidentiality Impact:	None
Integrity Impact:	High
Availability Impact:	None

Errata information

Platform	Errata	Release Date
Oracle Linux version 10 (rust-rpm-sequoia)	ELSA-2026-76734	2026-10-06
Oracle Linux version 10 (rust-sequoia-sqv)	ELSA-2026-76735	2026-10-06