CVE-2026-21575 in Sourcetree for Mac
Summary
by MITRE • 07/21/2026
This High severity RCE (Remote Code Execution) vulnerability was introduced in version 3.4.11 of Sourcetree for Mac and Sourcetree for Windows. This RCE (Remote Code Execution) vulnerability, with a CVSS Score of 7.1, allows an authenticated attacker to execute arbitrary code which has high impact to confidentiality, high impact to integrity, high impact to availability, and requires user interaction. Atlassian recommends that Sourcetree for Mac and Sourcetree for Windows customers upgrade to latest version, if you are unable to do so, upgrade your instance to one of the specified supported fixed versions: * Sourcetree for Mac and Sourcetree for Windows 3.4: Upgrade to a release greater than or equal to 3.4.13 See the release notes (https://www.sourcetreeapp.com/download-archives). You can download the latest version of Sourcetree for Mac and Sourcetree for Windows from the download center (https://www.sourcetreeapp.com/download-archives). This vulnerability was reported via our Bug Bounty program.
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Analysis
by VulDB Data Team • 07/21/2026
This remote code execution vulnerability in Atlassian Sourcetree affects versions 3.4.11 and earlier across both Mac and Windows platforms, representing a critical security flaw that enables authenticated attackers to execute arbitrary code on affected systems. The vulnerability carries a CVSS score of 7.1 and demonstrates high impact across all three core security principles: confidentiality, integrity, and availability. The threat model requires user interaction, suggesting that an attacker must first gain authentication credentials or trick a user into performing specific actions that trigger the exploit. This characteristic places the vulnerability in the context of privilege escalation attacks where initial access is gained through social engineering or credential compromise before executing malicious code.
The technical implementation of this vulnerability stems from improper input validation and sanitization within the application's handling of certain user-provided data streams. When users interact with specific features that process external inputs, the application fails to properly validate or escape these inputs before processing them, creating an attack surface where malicious payloads can be executed in the context of the running application. This class of vulnerability aligns with CWE-74, which describes improper neutralization of special elements used in data queries, and CWE-121, which covers stack-based buffer overflow conditions. The exploitation process likely involves crafting specially formatted inputs that bypass validation mechanisms and are subsequently processed by the application's underlying code execution engine.
Operational impact analysis reveals significant consequences for organizations using affected Sourcetree versions, as successful exploitation could lead to complete system compromise and data exfiltration. The vulnerability affects both desktop operating systems, indicating a widespread attack surface across different environments. Organizations may experience unauthorized access to version control repositories, potential code injection into source code management systems, and escalation of privileges that could allow attackers to move laterally within network environments. The requirement for user interaction suggests that targeted phishing campaigns or social engineering attacks could be employed to trigger the vulnerability, making it particularly dangerous in enterprise environments where developers frequently interact with repository management tools.
Mitigation strategies should prioritize immediate upgrading to version 3.4.13 or later releases as recommended by Atlassian, which contains patches addressing the identified security flaw. Organizations unable to perform immediate upgrades should implement network-level controls such as firewall rules that restrict access to the application's network services and monitor for suspicious activity patterns. The vulnerability reporting through Atlassian's Bug Bounty program indicates responsible disclosure practices were followed, allowing for coordinated remediation efforts rather than public exploitation. Security teams should also conduct comprehensive vulnerability assessments of their Sourcetree installations and implement monitoring solutions that can detect anomalous code execution patterns or unauthorized access attempts to version control systems. The ATT&CK framework categorizes this vulnerability under T1059 for command and scripting interpreter and potentially T1078 for valid accounts, as attackers would likely leverage legitimate user credentials to exploit the vulnerability.