Check Point Warns of Management Server Zero-Day Exploited in Targeted Attacks

CVE-2026-85102 is an improper certificate trust-validation flaw (CWE-295) in the VPN negotiation code of Check Point Quantum Security Gateways. An unauthenticated remote attacker who can reach the gateway's VPN service can trigger the flaw during VPN negotiation, where certificates involved in the exchange are not properly validated, and achieve code execution on the gateway. Successful exploitation yields arbitrary code execution on the gateway with high impact on confidentiality, integrity, and availability (CVSS 9.8), amounting to full compromise of the security gateway. The affected population is organizations running Quantum Security Gateways with VPN services reachable from untrusted networks. As of the available reporting there is no public proof-of-concept, the flaw is not in CISA's Known Exploited Vulnerabilities catalog, and no in-the-wild exploitation is confirmed; the issue was disclosed alongside a second, similarly rated (9.8) Check Point VPN certificate-validation RCE flaw.

Do: Upgrade Quantum Security Gateways to the fixed versions listed in Check Point's advisory (AV26-902) as soon as they are published, prioritizing internet-facing VPN gateways. Until patched, restrict exposure of VPN negotiation endpoints to trusted networks and monitor VPN services for anomalous handshake activity. Inventory which gateways in your estate expose VPN services publicly and treat those as the highest-priority targets.

CVE-2026-85103 is a heap-based buffer overflow (CWE-122) in the ASN.1 certificate-decoding code used by Check Point's VPN implementation, rated 9.8 Critical with a network-exploitable, unauthenticated, low-complexity vector. An unauthenticated remote attacker can trigger the flaw by sending crafted certificate data that the VPN service parses during connection handling, causing heap corruption that allows arbitrary code execution on the target system. Successful exploitation grants the attacker code execution with high confidentiality, integrity, and availability impact, which on security gateways and management servers could mean control of the security infrastructure itself. Any organization running Check Point Quantum Security Management or Quantum Security Gateway systems that process VPN certificate traffic is potentially affected, and the advisory set indicates this flaw was disclosed alongside a second, similarly rated 9.8 VPN certificate vulnerability (Check Point advisory AV26-902). There is no evidence of exploitation so far: the flaw is not in CISA's Known Exploited Vulnerabilities catalog and no public proof-of-concept is known.

Do: Patch promptly: because this is an unauthenticated, network-reachable 9.8-rated RCE in the VPN path, upgrade Quantum Security Management and Quantum Security Gateway deployments per Check Point's advisory (referenced as AV26-902), and check your current software versions against the affected/fixed ranges listed there, which are not specified in the data available here. Until patched, restrict access to exposed VPN and management interfaces to trusted source IPs where possible and monitor VPN endpoints for anomalous connection or crash behavior. Inventory all Quantum appliances and management servers, since the flaw affects both product lines and was disclosed together with a second 9.8 VPN certificate flaw.

CVE-2026-91843 is a stack-based buffer overflow (CWE-121) in the unauthenticated login process of a Check Point product, as Check Point Software (cve@checkpoint.com) is the assigning CNA and its CVE scope covers Check Point products. An attacker can trigger the flaw remotely by sending crafted input to the login interface before authenticating, with no user interaction or credentials required. Successful exploitation allows arbitrary code execution with root privileges, the highest level of control on the affected system. The vulnerability is rated 9.8 Critical (AV:N/AC:L/PR:N/UI:N, all impacts high), reflecting trivial network exploitability. No public proof-of-concept or confirmed in-the-wild exploitation is known at this time, and the source data does not name the specific product line or affected version ranges.

Do: Monitor Check Point's official advisory channels for the affected product/version list and patch release, and upgrade as soon as fixed versions are published. In the interim, restrict the login/management interface of Check Point appliances to trusted management networks and remove any direct internet exposure, and review perimeter logs for anomalous pre-authentication traffic against that interface.

This vulnerability allows an unauthenticated attacker to upload and execute arbitrary scripts on Check Point Management Server, achieving high confidentiality, integrity, and availability through directory traversal and file upload attacks. An attacker can leverage this flaw to compromise sensitive systems and gain extensive control over the management environment. The affected scope includes all Check Point Management Server installations, with no specific version range identified in the provided data.

Do: Upgrade to patched Check Point Management Server versions immediately; disable/block directory traversal and file upload features; audit all management server deployments and verify plugin installation status; monitor for new CVEs and update policies.