Check Point has warned of active exploitation of a critical vulnerability impacting Remote Access VPN and Mobile Access deployments that are configured to use the deprecated IKEv1 key exchange protocol.
The vulnerability, tracked as CVE-2026-50751 (CVSS score: 9.3), is a case of a logic flow weakness in certificate validation that allows an unauthenticated remote attacker to bypass user authentication and establish a remote access VPN connection without a valid user password.
"By exploiting a logic flaw in certificate validation, an attacker can establish a VPN session without possession of a valid password, effectively bypassing authentication requirements," Check Point said. "Additional post-authentication activity is required to access internal resources or escalate privileges."
The shortcoming impacts the following products and versions -
- Security Gateways R82.10 Jumbo Hotfix Take 19 or below, R82 Jumbo Hotfix Take 103 or below, R81.20 Jumbo Hotfix Take 141 or below, R81.10 (EOS), R81 (EOS), and R80.40 (EOS)
- Spark Firewalls: R80.20.X (EOS), R81.10.X, and R82.00.X
Successful exploitation requires the following conditions to be met -
- VPN Remote Access or Mobile Access is enabled
- IKEv1 is enabled for remote access
- Gateways accept legacy Remote Access clients
- Gateways do not demand a machine certificate for connections
The Israeli cybersecurity company said it first observed indications of suspicious activity on June 4, 2026, with the earliest observed exploitation dating back to May 7, 2026. Exploitation efforts are said to have ramped up starting this month.
The exploitation activity, Check Point added, has been limited to a "few dozen targeted organizations globally." In one case, the post-exploitation phase has been associated with a Qilin ransomware affiliate.
"We believe that this threat actor infrastructure is exploiting other VPN related vulnerabilities such as the ones published by Palo Alto [Networks], Fortinet, and F5," it noted. "We identified indicators suggesting the actor may use the Tox protocol for communication, a pattern commonly associated with financially motivated ransomware actors."
A key aspect is the use of a virtual private server (VPS) infrastructure to conduct the attacks. Specifically, this involves relying on VPS servers geolocated to a particular country to target organizations within its borders. Once access was established, the attackers were found attempting to download malicious ELF files from actor-controlled infrastructure.
Some aspects of these efforts overlap with a report from Ctrl-Alt-Intel last month, which highlighted the ransomware crew's abuse of corporate VPN appliances for initial access.
Further review of the affected VPN components has uncovered a second vulnerability, CVE-2026-50752 (CVSS score: 7.40), which may allow an adversary-in-the-middle (AitM) attack on VPN site-to-site connections. There is no evidence the flaw has been exploited in real-world attacks.
Found this article interesting? Follow us on Google News, Twitter and LinkedIn to read more exclusive content we post.