CVE-2023-35813: Sitecore Experience Commerce RCE Flaw

CVE-2023-35813 Overview

CVE-2023-35813 is a critical remote code execution (RCE) vulnerability affecting multiple Sitecore products. This vulnerability allows unauthenticated attackers to execute arbitrary code on affected Sitecore installations via network-based attacks. The flaw impacts Sitecore Experience Manager, Experience Platform, Experience Commerce, and Managed Cloud through version 10.3, potentially compromising the confidentiality, integrity, and availability of enterprise content management systems.

Critical Impact

Unauthenticated remote code execution vulnerability in Sitecore products through version 10.3 enables attackers to fully compromise affected systems without requiring any user interaction or authentication.

Affected Products

• Sitecore Experience Commerce (through 10.3)
• Sitecore Experience Manager (through 10.3)
• Sitecore Experience Platform (through 10.3)
• Sitecore Managed Cloud (through 10.3)

Discovery Timeline

• 2023-06-17 - CVE-2023-35813 published to NVD
• 2024-12-17 - Last updated in NVD database

Technical Details for CVE-2023-35813

Vulnerability Analysis

CVE-2023-35813 represents a code injection vulnerability (CWE-94) in multiple Sitecore products that enables remote code execution. The vulnerability can be exploited remotely without authentication, requiring no user interaction. Successful exploitation grants attackers the ability to execute arbitrary code on the underlying server with the privileges of the Sitecore application.

The attack surface is significant given that Sitecore products are enterprise-grade content management and digital experience platforms typically exposed to the internet. Organizations running vulnerable versions face risks of complete system compromise, data exfiltration, lateral movement within internal networks, and potential ransomware deployment.

Root Cause

The vulnerability stems from improper code injection controls (CWE-94) within the Sitecore platform. While specific technical details have not been publicly disclosed by the vendor, the classification indicates that user-supplied input is insufficiently validated before being processed in a context that allows code execution. This type of vulnerability typically occurs when application components process external data in ways that permit injection of executable code or commands.

Attack Vector

The attack vector is network-based, requiring no authentication or user interaction. An attacker can exploit this vulnerability by sending specially crafted requests to a vulnerable Sitecore instance accessible over the network. The low attack complexity combined with the lack of authentication requirements makes this vulnerability particularly dangerous for internet-facing Sitecore deployments.

Given that Sitecore platforms typically handle sensitive enterprise content and customer data, successful exploitation could lead to data breaches, service disruption, and further attacks against connected systems and databases.

Detection Methods for CVE-2023-35813

Indicators of Compromise

• Unexpected process spawning from Sitecore application pools or IIS worker processes
• Unusual outbound network connections from Sitecore servers to unknown external IP addresses
• Suspicious file creation or modification in Sitecore installation directories
• Anomalous entries in Sitecore application logs indicating code execution attempts

Detection Strategies

• Monitor IIS and Sitecore application logs for unusual request patterns targeting known exploitation paths
• Implement network intrusion detection signatures for Sitecore RCE exploitation attempts
• Deploy endpoint detection and response (EDR) solutions to identify malicious process chains originating from web application contexts
• Conduct regular vulnerability scanning of Sitecore installations to identify unpatched systems

Monitoring Recommendations

• Enable detailed logging for Sitecore applications and IIS to capture request parameters and response codes
• Configure SIEM rules to alert on potential code injection patterns in web application traffic
• Monitor for unauthorized changes to Sitecore configuration files and assemblies
• Track process creation events on Sitecore servers for child processes spawned by w3wp.exe

How to Mitigate CVE-2023-35813

Immediate Actions Required

• Identify all Sitecore installations in your environment running versions through 10.3
• Apply the security patches provided by Sitecore immediately for all affected products
• Restrict network access to Sitecore administration interfaces using firewall rules or network segmentation
• Review Sitecore server logs for any indicators of exploitation prior to patching

Patch Information

Sitecore has released security patches to address this vulnerability. Organizations should consult the Sitecore Knowledge Base Article KB1002979 for detailed patch information, affected version matrix, and upgrade guidance. Given the critical severity and network-exploitable nature of this vulnerability, patching should be treated as an emergency priority.

Workarounds

• Implement Web Application Firewall (WAF) rules to filter potentially malicious requests targeting Sitecore endpoints
• Place Sitecore instances behind a reverse proxy with strict input validation and request filtering
• Disable or restrict access to non-essential Sitecore features and endpoints until patches can be applied
• Isolate affected Sitecore servers on network segments with limited egress connectivity to reduce post-exploitation impact

# IIS configuration example - Restrict access to Sitecore admin interfaces
# Add to web.config or configure via IIS Manager
# Note: This is a temporary workaround until patching is complete

# Block external access to /sitecore path via IIS IP restrictions
# Configure in IIS Manager > IP Address and Domain Restrictions
# Deny access from all except trusted IP ranges