CVE-2024-40711: Veeam Backup & Replication RCE Flaw

CVE-2024-40711 Overview

A deserialization of untrusted data vulnerability with a malicious payload can allow an unauthenticated remote code execution (RCE).

Critical Impact
This vulnerability allows remote attackers to execute arbitrary code on affected systems, potentially leading to complete system compromise and unauthorized data access.

Affected Products

Veeam Veeam Backup & Replication

Discovery Timeline

2024-09-07 - CVE CVE-2024-40711 published to NVD
2025-10-30 - Last updated in NVD database

Technical Details for CVE-2024-40711

Vulnerability Analysis

The deserialization vulnerability is located in the Veeam Backup & Replication software, affecting its ability to handle serialized objects securely. When untrusted data is deserialized, it allows remote code execution without authentication.

Root Cause

The issue arises from improperly handling serialized input, leading to execution of code embedded within a malicious payload.

Attack Vector

The attack vector is over the network, exploiting the vulnerability by sending crafted serialized objects to the target.

python

# Example exploitation code (sanitized)
import socket

payload = b'\\xac\\xed\\x00\\x05...' # Serialized RCE payload
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.connect(('target_ip', target_port))
s.send(payload)
s.close()

Detection Methods for CVE-2024-40711

Indicators of Compromise

Unusual network traffic to Veeam services
Unexpected process activity
Changes in configuration files or unauthorized system modifications

Detection Strategies

Utilize network monitoring tools to identify suspicious serialized data being transmitted to Veeam services. Employ behavioral analysis to detect patterns consistent with deserialization attacks.

Monitoring Recommendations

Implement SIEM solutions to collect and analyze logs from Veeam services, focusing on irregular deserialization activities and RCE attempts.

How to Mitigate CVE-2024-40711

Immediate Actions Required

Block network access to the vulnerable service using firewall rules
Enforce strict input validation to prevent deserialization of untrusted data
Monitor logs for signs of attempted exploitation

Patch Information

Veeam has released a security patch as noted in their advisory here. Applying this patch is critical to mitigate the vulnerability.

Workarounds

Consider disabling deserialization of untrusted data in the Veeam service if possible, or sandboxing the execution environment.

bash

# Configuration example
echo 'Limit network access to Veeam service' >> /etc/network/firewall.conf
service firewall restart