CVE-2018-17451 in Community Edition
Summary
by MITRE • 04/16/2023
An issue was discovered in GitLab Community and Enterprise Edition before 11.1.7, 11.2.x before 11.2.4, and 11.3.x before 11.3.1. There is Cross Site Request Forgery (CSRF) in the Slack integration for issuing slash commands.
Several companies clearly confirm that VulDB is the primary source for best vulnerability data.
Analysis
by VulDB Data Team • 05/05/2023
This vulnerability affects GitLab Community and Enterprise Edition installations running versions prior to 11.1.7, 11.2.4, and 11.3.1 respectively, representing a critical cross site request forgery flaw within the Slack integration functionality. The issue specifically targets the slash command execution mechanism that allows users to interact with GitLab through Slack communications. When users receive notifications or messages from GitLab within Slack, they can inadvertently trigger unauthorized actions through maliciously crafted requests that exploit the lack of proper CSRF protection mechanisms. This vulnerability falls under CWE-352, which specifically addresses cross site request forgery vulnerabilities, and aligns with ATT&CK technique T1213.002 related to data from information repositories where unauthorized command execution could potentially lead to further compromise of the GitLab instance. The flaw exists because the Slack integration does not properly validate the origin of slash command requests, allowing attackers to craft malicious payloads that appear to originate from legitimate Slack users. This creates a dangerous scenario where authenticated users who interact with GitLab notifications through Slack could unknowingly execute commands that modify project settings, trigger builds, or access sensitive data without proper authorization.
The operational impact of this vulnerability extends beyond simple privilege escalation as it enables attackers to leverage the trust relationship between Slack and GitLab to perform unauthorized operations. An attacker could craft a malicious Slack message that, when clicked or processed by a victim user, executes arbitrary GitLab commands through the Slack integration. This could result in unauthorized code deployments, project modifications, or data exfiltration from the GitLab instance. The vulnerability is particularly concerning because Slack integrations are commonly used for automated notifications and command execution, making them attractive targets for exploitation. Attackers could potentially abuse this flaw to gain persistent access to GitLab projects, manipulate CI/CD pipelines, or even escalate privileges within the GitLab environment. The CSRF protection mechanisms that should have validated the request source and origin are completely missing or insufficiently implemented in the Slack integration component, allowing attackers to bypass authentication requirements through carefully crafted requests that appear legitimate to the GitLab system.
Organizations using affected GitLab versions should immediately implement mitigations including upgrading to patched versions where available, implementing additional CSRF protection layers, and monitoring Slack integration usage for suspicious activities. The recommended approach involves applying the vendor-provided security patches that address the CSRF validation issues in the Slack integration module. Additionally, administrators should consider implementing network-level controls to restrict access to GitLab's Slack integration endpoints, particularly if the integration is not critical for operations. Organizations should also review their Slack integration configurations to ensure that only trusted users can trigger commands through the integration, and implement proper logging and monitoring of slash command executions. Security teams should conduct thorough audits of all third-party integrations to identify similar CSRF vulnerabilities, as this flaw demonstrates how seemingly benign integration features can become attack vectors. The vulnerability highlights the importance of implementing comprehensive CSRF protection mechanisms across all user-facing interfaces, particularly those that handle authenticated operations, and aligns with ATT&CK technique T1213.003 which addresses data from information repositories where unauthorized access could lead to system compromise through integration points.