CVE-2026-21571

CVE-2026-21571 is a high-severity vulnerability rated 8.8/10 on the CVSS scale. This Critical severity OS Command Injection vulnerability was introduced in versions 9.6.0, 10.0.0, 10.1.0, 10.2.0, 11.0.0, 11.1.0, 12.0.0, and 12.1.0 of Bamboo Data Center.   This RCE (Remote Code Execution) vulnerability, with a CVSS Score of 9.4 and a CVSS Vector of CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H allows an authenticated attacker to execute commands on the remote system, which has high impact to confidentiality, high impact to integrity, high impact to availability, and requires no user interaction.   Atlassian recommends that Bamboo Data Center customers upgrade to latest version, if you are unable to do so, upgrade your instance to one of the specified supported fixed versions: Bamboo Data Center 9.6.0: Upgrade to a release greater than or equal to 9.6.25 Bamboo Data Center 10.2: Upgrade to a release greater than or equal to 10.2.18  Bamboo Data Center 12.1: Upgrade to a release greater than or equal to 12.1.6 See the release notes ([https://confluence.atlassian.com/bambooreleases/bamboo-release-notes-1189793869.html]). You can download the latest version of Bamboo Data Center from the download center ([https://www.atlassian.com/software/bamboo/download-archives]).. EPSS estimates a 1.27% chance of exploitation in the next 30 days.