Critical Veeam CVE actively exploited in ransomware attacks

Dive Brief:

Threat groups are actively exploiting a critical vulnerability in Veeam Backup and Replication for ransomware attacks, researchers and federal cyber authorities said. Veeam disclosed the vulnerability, which has a CVSS score of 9.8, in a Sept. 4 security bulletin along with five other vulnerabilities in the enterprise backup software.
The Cybersecurity and Infrastructure Security Agency added CVE-2024-40711 to its known exploited vulnerabilities catalog on Thursday and said it’s known to be used in ransomware attacks. The deserialization vulnerability allows an unauthenticated attacker to perform remote code execution.
Researchers at Sophos X-Ops tracked at least four ransomware attacks involving CVE-2024-40711 exploits earlier this month. The cybersecurity vendor’s threat response team said it observed attacks linked to Akira and Fog ransomware variants. “In each of the cases, attackers initially access targets using compromised VPN gateways without multifactor authentication enabled,” Sophos X-Ops said in an Oct. 11 post on social platform X.

Dive Insight:

Exploits and ransomware attacks linked to CVE-2024-40711 follow a common sequence, underscoring the sustained exposure and longtail impact of software vulnerabilities.

Veeam patched the vulnerability in a software update, Veeam Backup and Replication v12.2, on Aug. 28, version 12.2, Heidi Monroe Kroft, senior director of corporate communications and global public relations at Veeam, said via email Monday. “This was directly communicated to all impacted Veeam customers.”

Vulnerability researchers from Censys and Rapid7 sounded the alarm after the critical software defect in the popular enterprise product was patched and disclosed. Partial proof-of-concept exploit code was released within days of the public CVE disclosure.

Sophos X-Ops began tracking active exploits involving ransomware more than a month after Veeam resolved the vulnerability in a software update. CVE-2024-40711 affects Veeam Backup and Replication version 12.1.2.172 and prior version 12 builds.

The application is used by enterprises to backup, replicate and restore virtual, physical and cloud machines.

“As a result of its popularity, it's also a prime target for adversaries, including ransomware groups,” Caitlin Condon, director of vulnerability intelligence at Rapid7, said Monday via email. “More than 20% of Rapid7 incident response cases in 2024 have involved Veeam being accessed or exploited in some manner, typically once an adversary has already established a foothold in the target environment.”

Threat groups exploited previous Veeam Backup and Replication vulnerabilities months after disclosure, and almost a year later in one case, Condon said.

Veeam declined to say how many customers have patched or been impacted by the vulnerability.

Himaja Motheram, security researcher at Censys, said the number of exposed Veeam Backup and Replication servers has remained fairly consistent since the CVE was disclosed, dropping from 2,833 exposed instances on Sept. 6 to 2,784 exposed hosts as of Monday.

The exposed instances are mostly concentrated in Europe, according to Censys. The digital arm of the U.K.’s National Health Service issued a cybersecurity alert about active exploitation of CVE-2024-40711 on Oct. 11.