There is a command injection vulnerability using environment variables in Bitbucket Server and Data Center. An attacker with permission to control their username can exploit this issue to execute arbitrary code on the system. This vulnerability can be unauthenticated if the Bitbucket Server and Data Center instance has enabled “Allow public signup”.

Multiple API endpoints in Atlassian Bitbucket Server and Data Center 7.0.0 before version 7.6.17, from version 7.7.0 before version 7.17.10, from version 7.18.0 before version 7.21.4, from version 8.0.0 before version 8.0.3, from version 8.1.0 before version 8.1.3, and from version 8.2.0 before version 8.2.2, and from version 8.3.0 before 8.3.1 allows remote attackers with read permissions to a public or private Bitbucket repository to execute arbitrary code by sending a malicious HTTP request. This vulnerability was reported via our Bug Bounty Program by TheGrandPew.

A vulnerability in multiple Atlassian products allows a remote, unauthenticated attacker to cause additional Servlet Filters to be invoked when the application processes requests or responses. Atlassian has confirmed and fixed the only known security issue associated with this vulnerability: Cross-origin resource sharing (CORS) bypass. Sending a specially crafted HTTP request can invoke the Servlet Filter used to respond to CORS requests, resulting in a CORS bypass. An attacker that can trick a user into requesting a malicious URL can access the vulnerable application with the victim’s permissions. Atlassian Bamboo versions are affected before 8.0.9, from 8.1.0 before 8.1.8, and from 8.2.0 before 8.2.4. Atlassian Bitbucket versions are affected before 7.6.16, from 7.7.0 before 7.17.8, from 7.18.0 before 7.19.5, from 7.20.0 before 7.20.2, from 7.21.0 before 7.21.2, and versions 8.0.0 and 8.1.0. Atlassian Confluence versions are affected before 7.4.17, from 7.5.0 before 7.13.7, from 7.14.0 before 7.14.3, from 7.15.0 before 7.15.2, from 7.16.0 before 7.16.4, from 7.17.0 before 7.17.4, and version 7.21.0. Atlassian Crowd versions are affected before 4.3.8, from 4.4.0 before 4.4.2, and version 5.0.0. Atlassian Fisheye and Crucible versions before 4.8.10 are affected. Atlassian Jira versions are affected before 8.13.22, from 8.14.0 before 8.20.10, and from 8.21.0 before 8.22.4. Atlassian Jira Service Management versions are affected before 4.13.22, from 4.14.0 before 4.20.10, and from 4.21.0 before 4.22.4.

A vulnerability in multiple Atlassian products allows a remote, unauthenticated attacker to bypass Servlet Filters used by first and third party apps. The impact depends on which filters are used by each app, and how the filters are used. This vulnerability can result in authentication bypass and cross-site scripting. Atlassian has released updates that fix the root cause of this vulnerability, but has not exhaustively enumerated all potential consequences of this vulnerability. Atlassian Bamboo versions are affected before 8.0.9, from 8.1.0 before 8.1.8, and from 8.2.0 before 8.2.4. Atlassian Bitbucket versions are affected before 7.6.16, from 7.7.0 before 7.17.8, from 7.18.0 before 7.19.5, from 7.20.0 before 7.20.2, from 7.21.0 before 7.21.2, and versions 8.0.0 and 8.1.0. Atlassian Confluence versions are affected before 7.4.17, from 7.5.0 before 7.13.7, from 7.14.0 before 7.14.3, from 7.15.0 before 7.15.2, from 7.16.0 before 7.16.4, from 7.17.0 before 7.17.4, and version 7.21.0. Atlassian Crowd versions are affected before 4.3.8, from 4.4.0 before 4.4.2, and version 5.0.0. Atlassian Fisheye and Crucible versions before 4.8.10 are affected. Atlassian Jira versions are affected before 8.13.22, from 8.14.0 before 8.20.10, and from 8.21.0 before 8.22.4. Atlassian Jira Service Management versions are affected before 4.13.22, from 4.14.0 before 4.20.10, and from 4.21.0 before 4.22.4.

SharedSecretClusterAuthenticator in Atlassian Bitbucket Data Center versions 5.14.0 and later before 7.6.14, 7.7.0 and later prior to 7.17.6, 7.18.0 and later prior to 7.18.4, 7.19.0 and later prior to 7.19.4, and 7.20.0 allow a remote, unauthenticated attacker to execute arbitrary code via Java deserialization.