CVE-2024-7957: Danswer ZulipConnector Path Traversal Flaw

CVE-2024-7957 Overview

An arbitrary file overwrite vulnerability exists in the ZulipConnector component of danswer-ai/danswer, a popular AI-powered enterprise search and chat application. The vulnerability affects the latest version and stems from improper handling of user-controlled input in the load_credentials method. Attackers can exploit this flaw to overwrite or create arbitrary files on the target system when a zuliprc- directory already exists in the temporary directory.

Critical Impact

This vulnerability allows unauthenticated remote attackers to overwrite arbitrary files on the system, potentially leading to complete system compromise, denial of service, or execution of malicious code through overwritten configuration or executable files.

Affected Products

• danswer-ai/danswer (latest version)
• ZulipConnector component within danswer

Discovery Timeline

• 2025-03-20 - CVE-2024-7957 published to NVD
• 2025-03-20 - Last updated in NVD database

Technical Details for CVE-2024-7957

Vulnerability Analysis

This vulnerability is classified as CWE-29 (Path Traversal: '..\filename'), which indicates a path traversal weakness where user-supplied input is used to construct file paths without proper sanitization. The flaw exists within the load_credentials method of the ZulipConnector component, where two parameters—realm_name and zuliprc_content—are directly used to construct file paths and write file contents.

The attack requires no authentication and can be executed remotely over the network. Successful exploitation does not impact confidentiality but has high impact on both integrity and availability of the affected system. An attacker could overwrite critical system files, configuration files, or application data, leading to service disruption or system compromise.

Root Cause

The root cause of this vulnerability lies in insufficient input validation and sanitization within the load_credentials method. The realm_name parameter is used directly in file path construction without proper validation to prevent directory traversal sequences. Similarly, zuliprc_content is written to files without proper restrictions on where files can be created.

The vulnerability is conditional on the pre-existence of a zuliprc- directory in the temporary directory, which serves as the base path for file operations. When this directory exists, an attacker can manipulate the realm_name parameter to traverse outside the intended directory and overwrite arbitrary files on the filesystem.

Attack Vector

The attack vector is network-based and requires no user interaction or prior authentication. An attacker can craft malicious requests to the ZulipConnector endpoint, supplying specially crafted values for realm_name containing path traversal sequences (such as ../) to escape the intended directory structure.

The exploitation flow involves:

1. Identifying a target instance with the zuliprc- directory present in the temp directory
2. Crafting a request with a malicious realm_name containing directory traversal sequences
3. Including arbitrary content in zuliprc_content to be written to the target file
4. Submitting the request to overwrite or create files at arbitrary locations

For detailed technical information and proof of concept, refer to the Huntr Bounty Report.

Detection Methods for CVE-2024-7957

Indicators of Compromise

• Unexpected file modifications in system directories or application configuration paths
• Presence of files with unusual names or content in the zuliprc- temporary directory
• Web server logs showing requests to ZulipConnector endpoints with path traversal sequences (e.g., ../, ..%2f)
• Unexplained creation of files outside the expected temporary directory structure

Detection Strategies

• Implement web application firewall (WAF) rules to detect and block path traversal patterns in request parameters
• Monitor file system integrity for unexpected modifications to critical files and directories
• Analyze application logs for suspicious load_credentials method invocations with unusual realm_name values
• Deploy endpoint detection and response (EDR) solutions to identify anomalous file write operations

Monitoring Recommendations

• Enable comprehensive logging for all file system operations within the danswer application
• Set up alerts for any file creation or modification events outside the designated temporary directory
• Monitor for process behavior anomalies where the danswer application writes to unexpected paths
• Implement real-time file integrity monitoring for critical system and application files

How to Mitigate CVE-2024-7957

Immediate Actions Required

• Review and restrict file system permissions for the danswer application process to minimize the impact of potential exploitation
• Implement input validation on the realm_name parameter to reject any path traversal sequences
• Consider temporarily disabling the ZulipConnector functionality if not actively required
• Audit existing files in the zuliprc- temporary directory for any signs of compromise

Patch Information

At the time of publication, users should monitor the official danswer-ai/danswer repository for security patches addressing this vulnerability. Consult the Huntr Bounty Report for the latest remediation guidance and check for vendor advisories.

Workarounds

• Implement a reverse proxy or WAF rule to sanitize incoming requests and block path traversal patterns
• Restrict the danswer application's file system access using containerization or operating system-level access controls
• Remove or restrict access to the zuliprc- temporary directory if ZulipConnector functionality is not required
• Apply principle of least privilege to the service account running the danswer application

# Example: Restrict file system permissions for the danswer temp directory
chmod 700 /tmp/zuliprc-*
chown danswer:danswer /tmp/zuliprc-*

# Example: Add WAF rule to block path traversal (ModSecurity example)
SecRule ARGS "@contains ../" "id:1001,phase:2,deny,status:403,msg:'Path Traversal Attempt Blocked'"