Check Point Patches Two Critical VPN Vulnerabilities Allowing Unauthenticated Remote Code Execution
Check Point has addressed two critical vulnerabilities impacting its Security Gateway, Security Management Server, and locally managed Spark Firewall. Both issues carry a CVSS score of 9.8 and permit unauthenticated remote code execution.
The first flaw, CVE-2026-85102, lies in the certificate trust validation process during VPN negotiation. An attacker can force the negotiation and run arbitrary code on the Security Gateway.
The second vulnerability, CVE-2026-85103, is a heap-based buffer overflow that occurs when parsing the ASN.1 structure of certificates used in VPN connections. Exploitation requires sending a specially crafted certificate.
Affected releases include R81.20, R82, and R82.10 prior to the respective hotfixes, along with the unsupported R80.40 and R81 lines. Version R82.20 is not impacted. Patches are available in R82.10 Take 44, R82 Take 126, R81.20 Take 166, and dedicated builds for Spark Firewall.
Environments with Live Patch enabled received automatic protection starting September 9. For site-to-site VPN, administrators can temporarily disable implicit VPN rules and restrict UDP ports 500 and 4500 to known addresses. No workaround exists for remote access VPN or locally managed Spark Firewall.
The vulnerabilities were identified by Check Point’s own research team. As of the September 10 disclosure, the company reported no evidence of active exploitation or publicly available proof-of-concept code.
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