CVE-2024-21677: Confluence Data Center Path Traversal Flaw

CVE-2024-21677 Overview

CVE-2024-21677 is a high severity Path Traversal vulnerability affecting Atlassian Confluence Data Center and Server products. Introduced in version 6.13.0, this vulnerability allows an unauthenticated attacker to exploit a path traversal flaw that can result in high impact to confidentiality, integrity, and availability of the affected system. The attack requires user interaction but can be executed remotely over the network.

Atlassian has acknowledged this vulnerability through their Bug Bounty program and recommends that customers upgrade to the latest versions of Confluence Data Center and Server to remediate the risk.

Critical Impact

Unauthenticated attackers can exploit this path traversal vulnerability to potentially access sensitive files, modify system data, or disrupt service availability on affected Confluence instances.

Affected Products

• Atlassian Confluence Data Center (versions from 6.13.0)
• Atlassian Confluence Server (versions from 6.13.0)

Discovery Timeline

• 2024-03-19 - CVE-2024-21677 published to NVD
• 2025-03-13 - Last updated in NVD database

Technical Details for CVE-2024-21677

Vulnerability Analysis

This Path Traversal vulnerability (CWE-22) enables an unauthenticated attacker to access files and directories outside of the intended directory structure within Confluence Data Center and Server installations. The flaw was introduced in version 6.13.0 and affects subsequent versions until patched.

Path traversal attacks typically exploit insufficient input validation in file path handling, allowing attackers to use special character sequences like ../ to navigate the file system hierarchy. In the context of Confluence, successful exploitation could allow an attacker to read sensitive configuration files, access stored credentials, or potentially write malicious content to the server.

The attack vector is network-based with low complexity, though user interaction is required for successful exploitation. This suggests the vulnerability may be triggered through crafted links or content that a user must interact with within the Confluence interface.

Root Cause

The vulnerability stems from improper input validation and sanitization of file path parameters within Confluence Data Center and Server. The application fails to adequately restrict or validate user-supplied input that specifies file system paths, allowing directory traversal sequences to escape the intended directory boundaries.

This type of vulnerability typically occurs when applications construct file paths using concatenation of user input without proper canonicalization or validation checks for path traversal patterns.

Attack Vector

The attack is conducted remotely over the network without requiring authentication to the Confluence instance. However, user interaction is necessary, indicating that exploitation likely involves social engineering or requires a legitimate user to trigger the vulnerable code path.

An attacker would craft a malicious request containing path traversal sequences designed to access files outside the web application's root directory. The traversal sequences bypass intended access restrictions, potentially exposing sensitive system files, configuration data, or enabling further attacks on the underlying server.

Since no verified proof-of-concept code is available, the specific exploitation mechanism involves manipulating file path parameters in requests to the Confluence server. Technical details can be found in the Atlassian Security Advisory and JIRA Issue CONFSERVER-94604.

Detection Methods for CVE-2024-21677

Indicators of Compromise

• HTTP requests containing path traversal sequences such as ../, ..%2f, %2e%2e/, or similar encoded variants targeting Confluence endpoints
• Unusual file access patterns in server logs showing attempts to access files outside the Confluence application directory
• Web server logs indicating requests with abnormally long file paths or repeated parent directory references
• Access attempts to sensitive system files like /etc/passwd, configuration files, or application credential stores

Detection Strategies

• Implement web application firewall (WAF) rules to detect and block requests containing path traversal patterns
• Configure intrusion detection systems (IDS) to alert on HTTP requests with directory traversal sequences targeting Confluence servers
• Enable verbose logging on Confluence instances and monitor for suspicious file access patterns
• Deploy SentinelOne Singularity to detect anomalous file system access attempts and provide real-time protection against exploitation

Monitoring Recommendations

• Monitor Confluence access logs for requests containing encoded path traversal characters or unusual directory navigation patterns
• Set up alerts for failed file access attempts that indicate traversal outside expected directories
• Review application error logs for path-related exceptions that may indicate exploitation attempts
• Establish baseline file access patterns and alert on deviations that could indicate active exploitation

How to Mitigate CVE-2024-21677

Immediate Actions Required

• Upgrade Confluence Data Center to the latest available version immediately
• For Confluence Server customers, upgrade to the latest 8.5.x LTS version
• If immediate patching is not possible, implement network-level access controls to restrict access to trusted users and networks
• Deploy web application firewall rules to block path traversal attack patterns

Patch Information

Atlassian recommends that all Confluence Data Center and Server customers upgrade to the latest available versions. Fixed versions are documented in the Confluence Release Notes. The latest versions can be downloaded from the Atlassian Download Center.

For detailed patch information and affected version ranges, refer to the Atlassian Security Advisory.

Workarounds

• Restrict network access to Confluence servers using firewall rules to limit exposure to trusted IP ranges only
• Implement a reverse proxy with path validation rules to filter malicious traversal attempts before reaching Confluence
• Enable enhanced logging to detect exploitation attempts while awaiting patch deployment
• Consider temporarily disabling public access to Confluence until patches can be applied

# Example: Restrict Confluence access to trusted networks using iptables
# Adjust IP ranges according to your environment

# Allow access from internal network only
iptables -A INPUT -p tcp --dport 8090 -s 10.0.0.0/8 -j ACCEPT
iptables -A INPUT -p tcp --dport 8090 -s 192.168.0.0/16 -j ACCEPT
iptables -A INPUT -p tcp --dport 8090 -j DROP

# For HTTPS (if configured)
iptables -A INPUT -p tcp --dport 443 -s 10.0.0.0/8 -j ACCEPT
iptables -A INPUT -p tcp --dport 443 -s 192.168.0.0/16 -j ACCEPT
iptables -A INPUT -p tcp --dport 443 -j DROP