CVE-2017-18093 in FishEye
Summary
by MITRE
Various resources in Atlassian Fisheye and Crucible before version 4.4.3 (the fixed version for 4.4.x) and before 4.5.0 allow remote attackers who have permission to add or modify a repository to inject arbitrary HTML or JavaScript via a cross site scripting (XSS) vulnerability through the location setting of a configured repository.
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Analysis
by VulDB Data Team • 01/06/2020
The vulnerability CVE-2017-18093 represents a critical cross site scripting flaw in Atlassian Fisheye and Crucible platforms that affects versions prior to 4.4.3 and 4.5.0 respectively. This vulnerability resides in the repository configuration management functionality where attackers with sufficient privileges can manipulate the location setting of a configured repository to inject malicious content. The flaw enables remote attackers to execute arbitrary HTML or JavaScript code within the context of a victim's browser session, creating a significant security risk for organizations utilizing these code review and repository browsing tools.
The technical exploitation of this vulnerability occurs through the manipulation of repository location settings where user input is not properly sanitized or validated before being rendered in the web interface. This allows attackers who possess permissions to add or modify repositories to inject malicious payloads that persist in the application's data storage and are subsequently executed when other users view the affected repository information. The vulnerability demonstrates characteristics consistent with CWE-79 - Cross-site Scripting, specifically targeting the improper neutralization of input during web page generation. The flaw operates at the application layer where the platform fails to adequately filter or escape user-supplied data before incorporating it into dynamic web content, creating an attack surface that can be leveraged for session hijacking, data theft, or further privilege escalation.
The operational impact of this vulnerability extends beyond simple script execution as it can enable attackers to perform session manipulation attacks through the stolen session tokens that may be present in the victim's browser context. Organizations using Fisheye and Crucible may experience unauthorized access to sensitive code repositories, potential data exfiltration, and the ability to modify repository configurations to redirect users to malicious sites. The vulnerability particularly affects environments where multiple users have repository modification privileges, as it allows for the creation of persistent malicious entries that can compromise the integrity of the entire code review process. This type of vulnerability aligns with ATT&CK technique T1566 - Phishing, where attackers can leverage the platform's legitimate functionality to deliver malicious payloads to unsuspecting users. The attack vector requires minimal privileges, making it particularly dangerous as it can be exploited by users who have legitimate access to the repository management features but not necessarily elevated administrative rights.
Mitigation strategies for CVE-2017-18093 should prioritize immediate application of the vendor-provided patches to versions 4.4.3 and 4.5.0, which include proper input validation and sanitization mechanisms for repository location settings. Organizations should implement additional security controls including the restriction of repository modification privileges to only essential personnel, regular security audits of repository configurations, and the implementation of content security policies to limit the execution of unauthorized scripts. Network-based solutions such as web application firewalls can provide additional protection layers, while user education regarding suspicious repository entries and the verification of repository configurations can help prevent successful exploitation attempts. The vulnerability also underscores the importance of maintaining up-to-date security practices and regular vulnerability assessments for all development infrastructure tools to prevent similar issues from occurring in the future.