CVE-2023-22513: Bitbucket Data Center RCE Vulnerability

CVE-2023-22513 Overview

CVE-2023-22513 is a Remote Code Execution (RCE) vulnerability affecting Atlassian Bitbucket Data Center and Server. This vulnerability was introduced in version 8.0.0 and allows an authenticated attacker to execute arbitrary code on affected systems. The vulnerability has high impact to confidentiality, integrity, and availability, and requires no user interaction to exploit.

Bitbucket is a widely-used Git repository management solution for enterprise teams, making this vulnerability particularly concerning for organizations that rely on it for source code management and collaboration. Successful exploitation could allow attackers to gain complete control over the Bitbucket instance, potentially compromising sensitive source code repositories and development infrastructure.

Critical Impact

Authenticated attackers can execute arbitrary code on vulnerable Bitbucket Data Center and Server instances, potentially compromising source code repositories and development infrastructure.

Affected Products

• Atlassian Bitbucket Data Center versions 8.0.0 through 8.9.4
• Atlassian Bitbucket Data Center versions 8.10.0 through 8.10.4
• Atlassian Bitbucket Data Center versions 8.11.0 through 8.11.3
• Atlassian Bitbucket Data Center versions 8.12.0 through 8.12.1
• Atlassian Bitbucket Data Center version 8.13.0
• Atlassian Bitbucket Server versions 8.0.0 through 8.9.4
• Atlassian Bitbucket Server versions 8.10.0 through 8.10.4
• Atlassian Bitbucket Server versions 8.11.0 through 8.11.3
• Atlassian Bitbucket Server versions 8.12.0 through 8.12.1
• Atlassian Bitbucket Server version 8.13.0

Discovery Timeline

• 2023-09-19 - CVE-2023-22513 published to NVD
• 2025-03-06 - Last updated in NVD database

Technical Details for CVE-2023-22513

Vulnerability Analysis

This vulnerability is classified as CWE-94 (Improper Control of Generation of Code - Code Injection), indicating that the application fails to properly neutralize or incorrectly neutralizes code syntax before using it in a generated code segment. An authenticated attacker with access to the Bitbucket instance can leverage this flaw to inject and execute arbitrary code within the context of the application.

The attack can be conducted over the network and requires low attack complexity, meaning that once an attacker has valid authentication credentials, exploitation is straightforward. The vulnerability requires no user interaction beyond the attacker's actions, making it easier to exploit in automated attack scenarios.

Root Cause

The vulnerability stems from improper control of code generation within Bitbucket Data Center and Server. The application fails to properly validate or sanitize certain inputs that are subsequently used in code execution contexts. This code injection weakness allows authenticated users to introduce malicious code that gets executed by the application with the privileges of the Bitbucket service.

Attack Vector

The attack vector for CVE-2023-22513 is network-based, allowing remote exploitation. An attacker must first obtain valid authentication credentials for the Bitbucket instance, which could be achieved through credential theft, phishing, or using compromised developer accounts.

Once authenticated, the attacker can craft malicious requests that inject code into vulnerable application components. The injected code is then executed by the server, providing the attacker with arbitrary code execution capabilities. This could lead to complete system compromise, data exfiltration, lateral movement within the network, or establishment of persistent backdoors.

The vulnerability mechanism involves improper handling of user-controlled input that reaches code generation or execution functions. For detailed technical information about the specific attack vectors and exploitation methods, refer to the Atlassian Security Advisory.

Detection Methods for CVE-2023-22513

Indicators of Compromise

• Unusual process spawning from the Bitbucket Java process, particularly shell interpreters or system utilities
• Unexpected network connections originating from the Bitbucket server to external addresses
• Anomalous authentication patterns followed by suspicious API calls or repository operations
• Creation of unexpected files or modifications to system configurations on the Bitbucket server

Detection Strategies

• Monitor Bitbucket application logs for unusual error messages, stack traces, or code execution indicators
• Implement network detection rules to identify anomalous outbound connections from Bitbucket servers
• Deploy endpoint detection and response (EDR) solutions to monitor for suspicious process creation and file system activity on Bitbucket hosts
• Audit user authentication events and correlate with subsequent high-risk API calls

Monitoring Recommendations

• Enable verbose logging on Bitbucket Data Center and Server instances to capture detailed request information
• Configure SIEM rules to alert on code execution patterns or shell command indicators in application logs
• Establish baseline network traffic patterns for Bitbucket servers and alert on deviations
• Implement file integrity monitoring on critical Bitbucket server directories and configuration files

How to Mitigate CVE-2023-22513

Immediate Actions Required

• Identify all Bitbucket Data Center and Server instances in your environment running versions 8.0.0 through 8.13.0
• Prioritize patching based on exposure, with internet-facing instances receiving immediate attention
• Review access logs for signs of exploitation and audit user accounts with elevated privileges
• Consider temporary network isolation of vulnerable instances if immediate patching is not possible

Patch Information

Atlassian has released security patches to address this vulnerability. Organizations should upgrade to one of the following fixed versions:

• Bitbucket Data Center and Server 8.9: Upgrade to version 8.9.5 or later
• Bitbucket Data Center and Server 8.10: Upgrade to version 8.10.5 or later
• Bitbucket Data Center and Server 8.11: Upgrade to version 8.11.4 or later
• Bitbucket Data Center and Server 8.12: Upgrade to version 8.12.2 or later
• Bitbucket Data Center and Server 8.13: Upgrade to version 8.13.1 or later
• Bitbucket Data Center and Server 8.14: Upgrade to version 8.14.0 or later

For instances running versions 8.0.0 through 8.8.x, upgrade to any of the listed fix versions above. The latest version can be downloaded from the Atlassian Download Center. Release notes are available at the Atlassian Documentation.

Workarounds

• Restrict network access to Bitbucket instances using firewall rules or network segmentation to limit exposure
• Implement strict authentication controls and review user permissions to minimize the attack surface
• Enable and monitor audit logging to detect potential exploitation attempts
• Consider placing a web application firewall (WAF) in front of Bitbucket instances with rules to detect code injection attempts

# Example: Restrict network access to Bitbucket using iptables
# Allow access only from trusted networks
iptables -A INPUT -p tcp --dport 7990 -s 10.0.0.0/8 -j ACCEPT
iptables -A INPUT -p tcp --dport 7990 -j DROP

# Example: Check current Bitbucket version
cat /var/atlassian/application-data/bitbucket/shared/bitbucket.properties | grep version