CVE-2023-27532 Overview
CVE-2023-27532 is a missing authentication vulnerability (CWE-306) affecting Veeam Backup & Replication that allows unauthenticated attackers to obtain encrypted credentials stored in the configuration database. This vulnerability enables remote attackers to extract sensitive credential information from Veeam backup infrastructure, potentially leading to full compromise of backup systems and connected hosts.
Critical Impact
This vulnerability is actively exploited in the wild and has been added to CISA's Known Exploited Vulnerabilities (KEV) catalog. Attackers can leverage exposed credentials to gain unauthorized access to backup infrastructure hosts, potentially leading to data theft, ransomware deployment, or complete infrastructure compromise.
Affected Products
- Veeam Backup & Replication 11.0.1.1261 (all patch levels)
- Veeam Backup & Replication 12.0.0.1420
- All earlier versions of Veeam Backup & Replication
Discovery Timeline
- 2023-03-10 - CVE-2023-27532 published to NVD
- 2025-11-03 - Last updated in NVD database
Technical Details for CVE-2023-27532
Vulnerability Analysis
This vulnerability stems from a missing authentication mechanism in the Veeam Backup & Replication component that handles credential storage and retrieval. The affected component fails to properly verify authentication before returning encrypted credentials from the configuration database.
The vulnerability allows unauthenticated network access to sensitive credential data. While the credentials are encrypted, obtaining them provides attackers with material that can potentially be decrypted offline or used in further attacks against the backup infrastructure. The confidentiality impact is significant as sensitive authentication information is exposed without requiring any privileges or user interaction.
Root Cause
The root cause is classified as CWE-306: Missing Authentication for Critical Function. The Veeam Backup & Replication service exposes functionality that retrieves encrypted credentials from the configuration database without requiring proper authentication. This design flaw allows any network-accessible attacker to request and obtain sensitive credential information.
Attack Vector
The attack is network-based and requires no authentication, privileges, or user interaction to exploit. An attacker with network access to the Veeam Backup & Replication service can send specially crafted requests to extract encrypted credentials from the configuration database.
The exploitation flow typically involves:
- Identifying a vulnerable Veeam Backup & Replication instance accessible over the network
- Sending requests to the vulnerable component to retrieve stored credentials
- Obtaining encrypted credential material from the configuration database
- Using the extracted credentials to gain access to backup infrastructure hosts
Given the EPSS probability of 82.663% (99th percentile), this vulnerability has an extremely high likelihood of exploitation and should be prioritized for immediate remediation.
Detection Methods for CVE-2023-27532
Indicators of Compromise
- Unexpected network connections to Veeam Backup & Replication services from untrusted sources
- Unusual access patterns to the Veeam configuration database
- Authentication attempts to backup infrastructure hosts using credentials not recently rotated
- Network traffic on Veeam service ports (TCP 9401, 9392) from unauthorized systems
Detection Strategies
- Monitor network traffic for unauthorized connections to Veeam Backup & Replication services
- Implement network segmentation monitoring to detect lateral movement from backup infrastructure
- Deploy endpoint detection to identify credential dumping or unauthorized access attempts on backup hosts
- Enable comprehensive logging on Veeam services and correlate with SIEM for anomaly detection
Monitoring Recommendations
- Enable detailed audit logging for all Veeam Backup & Replication components
- Monitor authentication events across backup infrastructure hosts for signs of credential abuse
- Implement alerting for any access to Veeam services from non-management network segments
- Track and alert on configuration database access patterns for anomalies
How to Mitigate CVE-2023-27532
Immediate Actions Required
- Apply the security patch from Veeam immediately as detailed in KB4424
- Rotate all credentials stored in Veeam Backup & Replication configuration database
- Restrict network access to Veeam services to authorized management systems only
- Review backup infrastructure hosts for signs of unauthorized access or compromise
Patch Information
Veeam has released security updates to address CVE-2023-27532. Organizations should consult the Veeam Knowledge Base Article KB4424 for specific patch information and update instructions. Given this vulnerability's inclusion in the CISA Known Exploited Vulnerabilities Catalog, federal agencies are required to remediate according to CISA deadlines, and all organizations should treat this as an urgent priority.
Workarounds
- Implement strict firewall rules to block access to Veeam Backup & Replication services (TCP 9401, 9392) from untrusted networks
- Isolate backup infrastructure on a dedicated management network segment
- Use VPN or jump servers to restrict administrative access to Veeam systems
- Enable multi-factor authentication for all accounts with access to backup infrastructure
# Example firewall rules to restrict Veeam service access
# Allow only management subnet to access Veeam services
iptables -A INPUT -p tcp --dport 9401 -s 10.0.100.0/24 -j ACCEPT
iptables -A INPUT -p tcp --dport 9392 -s 10.0.100.0/24 -j ACCEPT
iptables -A INPUT -p tcp --dport 9401 -j DROP
iptables -A INPUT -p tcp --dport 9392 -j DROP
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
