CVE-2026-12816

This High severity BASM (Broken Authentication & Session Management) vulnerability known as CVE-2026-12816 was introduced in 9.12.1 and later of Jira Software Data Center and Server. This BASM (Broken Authentication & Session Management) vulnerability, with a CVSS Score of 8.7 and a CVSS Vector of CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:Amber allows an unauthenticated attacker to perform actions as another user. Atlassian recommends that Jira Software Data Center and Server customers upgrade to latest version, if you are unable to do so, upgrade your instance to one of the specified supported fixed versions: * Jira Software Data Center and Server 9.12: Upgrade to a release greater than or equal to 9.12.39 * Jira Software Data Center and Server 11.3: Upgrade to a release greater than or equal to 11.3.11 * Jira Software Data Center and Server 10.3: Upgrade to a release greater than or equal to 10.3.25 See the release notes (https://www.atlassian.com/software/jira/download-archives). You can download the latest version of Jira Software Data Center and Server from the download center (https://www.atlassian.com/software/jira/download-archives). The National Vulnerability Database provides the following description for this vulnerability: In Bouncy Castle for Java before 1.85, IESEngine stream-mode MAC forgery via length-dependent KDF split. This issue also affects Bouncy Castle for Java LTS before 2.73.12.

EPSS 0.18% · 6.9th percentile