Search: “FortiClient Windows”

CISA Warns of Fortinet Heap-based Buffer Overflow Flaw Exploited in Attacks

CISA added actively exploited Fortinet CVE-2025-25249, a critical heap-based buffer overflow in FortiOS, FortiSwitchManager, and FortiSASE, to its KEV catalog.

CVE-2025-25249 is a heap-based buffer overflow (CWE-122/CWE-787) allowing unauthorized code execution by sending specially crafted packets. CISA added it to the Known Exploited Vulnerabilities catalog on September 9, 2026, with a September 12 remediation deadline for federal agencies under BOD 26-04 and mandatory forensic triage of affected environments. Internet-facing Fortinet firewalls and SASE platforms are a likely foothold for credential theft, persistence, and lateral movement; ransomware use is currently listed as unknown.

Cyber Security News·Sep 10, 11:26 UTC · 6d agoExploit / PoC in the wild 4 sourcesCVE-2025-252492

Heap overflow in kernel driver due to missing size validation

Fortinet fixes a CVSS 7.3 heap overflow in the FortiClient Windows kernel driver enabling code execution via crafted DNS responses.

Fortinet PSIRT advisory FG-IR-26-156, revised 2026-08-12, describes a heap-based buffer overflow (CWE-120, buffer copy without checking input size) in the FortiClient Windows kernel driver, scored CVSSv3 7.3. An unauthenticated attacker positioned to alter or craft DNS responses for a targeted host could execute arbitrary code via malicious packets. No CVE identifier or exploitation status is provided in the advisory text, so administrators should check the full bulletin for affected versions and fixed releases.

Fortinet PSIRT·Aug 12, 07:00 UTC · Aug 12, 2026Advisory

Arbitrary process termination from exposed minifilter communication port

Fortinet FortiClient Windows fortimon3 driver flaw (CVSS 4.7) lets authenticated attackers terminate arbitrary processes via exposed minifilter communication port.

Fortinet advisory FG-IR-26-165 discloses an unverified ownership vulnerability (CWE-283, CVSSv3 4.7) in the FortiClient Windows fortimon3 minifilter driver. An authenticated attacker can terminate arbitrary processes through an exposed minifilter communication port. The advisory was revised on 2026-09-08.

Fortinet PSIRT·Sep 8, 07:00 UTC · 8d agoAdvisory1

Fortinet Patches Critical Vulnerabilities in FortiMonitorOnSight, Chrome Extension

Fortinet patched 10 vulnerabilities including two critical authentication flaws, CVE-2026-84390 (CVSS 9.6) and CVE-2026-84388 (CVSS 9.1), in FortiMonitorOnSight and the FortiPAM Chrome extension.

Fortinet's September patch release fixes CVE-2026-84390, a sensitive-information issue in the FortiMonitorOnSight web portal that lets unauthenticated attackers bypass authentication with forged or reused JWTs. CVE-2026-84388 is an improper authentication flaw in the Fortinet Privileged Access Agent Chrome extension that can allow attackers to proxy a user's browser traffic via a malicious website, requiring upgrades to both FortiPAM 1.9.1/1.8.4 and extension 8.0.1.123+. High-severity information disclosure in FortiSandbox (CVE-2026-26084) and man-in-the-middle risk in the FortiOS/FortiProxy Agentless ZTNA portal (CVE-2026-84393) were also fixed, alongside medium/low issues across FortiManager, FortiAnalyzer, FortiSOAR, FortiClient, FortiSIEM and others. Fortinet did not indicate any of the flaws are being exploited in the wild.

SecurityWeek·Sep 9, 14:33 UTC · 6d agoVulnerability 2 sourcesCVE-2026-84390CVE-2026-84388CVE-2026-26084+1 CVEs

12 Best Application Control & Allowlisting Tools Compared (2026): Features & Pricing

GBHackers compares twelve application allowlisting tools for 2026, naming ThreatLocker and Airlock Digital leaders and Microsoft WDAC the free native option.

GBHackers published an editorial comparison of twelve application control and allowlisting tools for 2026, assessing control depth, manageability, and pricing models. It ranks ThreatLocker and Airlock Digital as leading dedicated allowlisting options, positions Microsoft WDAC/AppLocker as the free native choice for Windows estates, and highlights CyberArk and BeyondTrust for coupling control with privilege management.

GBHackers·updated 09:52 UTC · 2h ago·first Sep 10, 08:24 UTC · 6d agoIndustry 13 sources1

Fortinet Vulnerability Ransomware

Ransomware operators are exploiting a Fortinet vulnerability, per the Infosecurity Magazine headline; article details unavailable.

Infosecurity Magazine's headline indicates ransomware activity tied to a Fortinet vulnerability. The article body was not available, so the specific CVE, affected versions and victim details are unconfirmed.

Infosecurity Magazine·Aug 16, 00:00 UTC · Aug 16, 2026Exploit / PoC in the wild

Top 10 Best Application Control & Allowlisting Tools in 2026

Roundup ranks 2026 application allowlisting tools, scoring ThreatLocker 8.8/10, Airlock Digital 8.5/10 and free Microsoft WDAC among top default-deny options.

This is a scored buyer's guide to ten application control and allowlisting tools for 2026, with ThreatLocker ranked first (8.8/10), Airlock Digital second (8.5/10) and Microsoft's built-in WDAC/AppLocker third (7.2/10). It notes ransomware has renewed interest in default-deny execution controls and that CISA and other agencies list application control among the most effective yet under-deployed mitigations. The evaluation is research-based with no lab testing, weighting policy automation at 30% and operability at 25%.

Cyber Security News·Sep 9, 07:59 UTC · 7d agoIndustry1

China-Linked Hackers Deploy New StormEncryptor Ransomware, Likely via N

The Hacker News·Aug 10, 16:38 UTC · Aug 10, 2026Ransomware in the wildCVE-2026-18577CVE-2026-18556CVE-2023-37679+7 CVEs

Workflow session email approval process bypass

Fortinet disclosed an improper access control flaw (CVSS 4.7) in FortiManager allowing administrators to bypass workflow session email approval via crafted HTTP requests.

Fortinet advisory FG-IR-26-171 covers an improper access control vulnerability (CWE-284) in FortiManager, rated CVSSv3 4.7. An administrator can bypass the approval process for workflow sessions via crafted HTTP or HTTPS requests. The advisory was revised on 2026-09-08.

Fortinet PSIRT·Sep 8, 07:00 UTC · 8d agoAdvisory

Broken access control in the RADIUS type admin group

FortiWeb RADIUS admin authentication flaw (CVSS 8.8) permits remote GUI/CLI login with random credentials under specific non-default settings.

Fortinet advisory FG-IR-26-158 describes an improper authentication flaw (CWE-287) in FortiWeb's Remote RADIUS-type admin authentication, scored CVSSv3 8.8. When the configuration uses specific non-default settings, a remote unauthenticated attacker can log into the FortiWeb GUI or CLI with a random username and password. The advisory was revised on 2026-08-12 and does not state that exploitation has been observed.

Fortinet PSIRT·Aug 12, 07:00 UTC · Aug 12, 2026Advisory

Weekly Cybersecurity Newsletter Bulletin – Microsoft 0-day, FortiOS, PAN-OS Flaw, Revolut Data Breach, and 20+ Stories

Weekly roundup: Microsoft patches 973 flaws including two actively exploited zero-days; FortiOS CAPWAP flaw deploys PivotC2 RAT; PAN-OS root RCE disclosed.

Microsoft's September 2026 Patch Tuesday fixed 973 vulnerabilities, including two zero-days under active exploitation: CVE-2026-85880 (Windows ALPC) and CVE-2026-81963 (Windows Update Stack), both elevation-of-privilege bugs. SOCRadar reported active exploitation of CVE-2025-25249 (CVSS 9.8) in FortiOS CAPWAP, deploying a Node.js RAT called PivotC2 that exfiltrates Exchange mailboxes to Wasabi cloud storage; 178 devices were compromised out of 30,000 scanned IPs, attributed to a Russian-speaking financially motivated group. Palo Alto disclosed CVE-2026-0310, a 9.2-rated buffer overflow enabling root code execution on PA-Series firewalls, and Fortinet disclosed CVE-2026-84393, a ZTNA certificate validation MITM flaw. Cyera also revealed CVE-2026-6471 ('PostGREShell'), a 12-year-old PostgreSQL logical-decoding flaw allowing code execution via REPLICATION-privileged accounts.

Cyber Security News·Sep 14, 03:10 UTC · 2d agoExploit / PoC in the wildCVE-2026-85880CVE-2026-81963CVE-2025-25249+3 CVEs3

Hackers Exploit Critical FortiGate Flaw to Deploy AI-Assisted PivotC2 RAT

SOCRadar says attackers exploit FortiGate CVE-2025-25249 to deploy the PivotC2 Node.js RAT, compromising 178 of 30,000 targeted devices and stealing credentials.

SOCRadar's Threat Research Unit reports active exploitation of CVE-2025-25249, a CVSS 9.8 heap-based buffer overflow in the cw_acd daemon of FortiOS and FortiSwitchManager, via crafted CAPWAP requests to UDP port 5246, compromising at least 178 of 30,000 targeted internet-exposed FortiGate devices since July 2026. The campaign deploys PivotC2, a Node.js RAT that provides interactive shells, SOCKS5/HTTP proxying, port forwarding, network scanning, and automated configuration harvesting that decrypts stored FortiGate credentials, including VPN pre-shared keys, SSL-VPN credentials, and LDAP secrets. Russian-language artifacts, AD enumeration, browser credential theft, RDP enablement, and exfiltration of Exchange .pst files to Wasabi S3 point to a Russian-speaking, financially motivated group; two US organizations confirmed full-network intrusions. Fixes include FortiOS 7.6.4/7.4.9/7.2.12/7.0.18+ and FortiSwitchManager 7.2.7/7.0.6+, plus blocking CAPWAP on internet-facing interfaces.

GBHackers·Sep 9, 08:57 UTC · 7d agoMalware in the wildCVE-2025-252492

Improper Authentication of FortiPAM Server

Fortinet discloses CVSS 9.1 improper authentication in FortiPAM's Chrome extension allowing unauthenticated attackers to proxy victims' browser traffic.

Fortinet advisory FG-IR-26-168 describes an improper authentication vulnerability (CWE-287) rated 9.1 in the Fortinet Privileged Access Agent Chrome Extension. A remote unauthenticated attacker could proxy a user's browser traffic through attacker-controlled servers if the user visits a malicious website. The advisory was revised on September 8, 2026.

Fortinet PSIRT·Sep 8, 07:00 UTC · 8d agoAdvisory

Server-Side Request Forgery (SSRF)

Fortinet discloses a low-severity SSRF in the FortiSIEM GUI allowing authenticated attackers to send requests from targeted devices.

Fortinet PSIRT advisory FG-IR-26-159, revised 2026-08-12, describes a server-side request forgery (CWE-918) in the FortiSIEM GUI, scored CVSSv3 3.4. An authenticated attacker can send HTTP requests originating from the targeted device via specially crafted requests, potentially enabling internal network probing. No CVE identifier or exploitation status is included in the advisory text.

Fortinet PSIRT·Aug 12, 07:00 UTC · Aug 12, 2026Advisory

UI DoS attack

FortiOS web interface is vulnerable to unauthenticated slow HTTP denial-of-service attacks via crafted requests (CVSS 5.0).

Fortinet advisory FG-IR-26-162 details an unbounded resource allocation flaw (CWE-770) in FortiOS, scored CVSSv3 5.0. An unauthenticated attacker can launch a slow HTTP denial-of-service attack against the FortiOS web interface using crafted HTTP requests. The advisory was revised on 2026-08-12 and does not state that exploitation has been observed.

Fortinet PSIRT·Aug 12, 07:00 UTC · Aug 12, 2026Advisory

Hackers Actively Exploiting FortiGate Firewalls to Deploy Custom Node.js Malware

Attackers actively exploit CVE-2025-25249 in FortiGate firewalls to deploy PivotC2, a Node.js RAT that decrypts VPN and admin credentials.

SOCRadar assesses with high confidence that threat actors are actively exploiting CVE-2025-25249, a CVSS 9.8 heap buffer overflow in the cw_acd daemon (CAPWAP, UDP 5246) affecting FortiOS 6.4-7.6.3 and FortiSwitchManager 7.0.x/7.2.x. Attackers deploy fortirun.bin and PivotC2, a Node.js post-exploitation framework that harvests configurations and decrypts SSL-VPN, wireless, and admin credentials using AES-256-CBC and AES-128-GCM. Over 30,000 FortiGate IPs were scanned and 178 devices compromised, including two confirmed full intrusions of US organizations with Exchange mailbox exfiltration to Wasabi storage. STRU attributes the campaign to a Russian-speaking, financially motivated cybercrime operator.

Cyber Security News·Sep 8, 16:50 UTC · 7d agoExploit / PoC in the wildCVE-2025-252491

Uncontrolled Resource Consumption in SNMP

Uninitialized variable flaw (CVSS 5.9) in FortiAnalyzer's SNMP daemon lets remote authenticated attackers cause denial of service via SNMP GETBULK requests.

Fortinet advisory FG-IR-26-172 describes a use of uninitialized variable vulnerability (CWE-457) in the FortiAnalyzer SNMP daemon, scored CVSSv3 5.9. A remote authenticated attacker with user-level permissions can cause a denial of service via SNMP GETBULK requests. The advisory was revised on 2026-09-08.

Fortinet PSIRT·Sep 8, 07:00 UTC · 8d agoAdvisory

U.S. CISA adds Arista VeloCloud Orchestrator and Fortinet FortiOS flaws to its Known Exploited Vulnerabilities catalog

Security Affairs·Aug 5, 15:24 UTC · Aug 5, 2026Exploit / PoC in the wildCVE-2025-68686CVE-2026-16812

FGFM Authentication Weakening via CLI Configuration

FortiManager FGFM flaw (CVSS 7.3) lets an attacker with a valid certificate impersonate any managed FortiGate under a specific CLI option.

Fortinet advisory FG-IR-26-160 describes an authentication bypass via alternate path (CWE-288) in FortiManager and FortiManager Cloud, scored CVSSv3 7.3. A remote unauthenticated attacker holding a valid certificate can impersonate any FortiGate managed by the affected FortiManager when a specific CLI option is set. The impersonation is performed with crafted FGFM protocol requests. The advisory was revised on 2026-08-12 and does not report active exploitation.

Fortinet PSIRT·Aug 12, 07:00 UTC · Aug 12, 2026Advisory

Gunra Ransomware Exploits Fortinet FortiOS, FortiProxy Flaws to Breach Networks

CISA, FBI, and South Korean agencies warn Gunra ransomware, with 51 victims since April 2025, exploits Fortinet flaws for double-extortion attacks on critical infrastructure.

CISA, the FBI, and South Korean agencies warned of Gunra ransomware attacks targeting healthcare, financial services, government, and professional services worldwide. The Conti-derived operation exploits internet-facing Fortinet FortiOS and FortiProxy flaws CVE-2024-55591 and CVE-2025-24472 for initial access, then deploys double extortion with Salsa20/ChaCha20 encryption and publishes non-payers on a leak site within five to seven days. Ransomware.Live lists 51 victims since April 2025, mostly in South Korea, Brazil, Spain, Thailand, and Hong Kong. The group uses Impacket tools for SMB lateral movement and NTDS credential dumping, tampers with VDI authentication to accept a designated OTP value to bypass MFA, and launched a RaaS affiliate program in January 2026 under the new alias Golden Community.

The Hacker News·Aug 12, 08:42 UTC · Aug 12, 2026Ransomware in the wildCVE-2024-55591CVE-2025-24472

11 Best CSPM Tools Compared (2026): Features & Pricing

CSPM comparison ranks Wiz first for agentless attack-path analysis; notes Ermetic absorbed into Tenable and Lacework into Fortinet FortiCNAPP.

An editorial comparison of eleven CSPM tools ranks Wiz as the agentless attack-path momentum leader, Prisma Cloud as the breadth benchmark, and Orca as the agentless SideScanning pioneer. It highlights consolidation: Ermetic now powers Tenable Cloud Security and Lacework became Fortinet's FortiCNAPP. The guide recommends starting with free tiers from Defender for Cloud, Prowler, and native cloud tools before buying.

GBHackers·Sep 15, 06:37 UTC · 1d agoIndustry1

Fortra security advisory (AV26-906)

Canada's Cyber Centre advises that Fortra GoAnywhere MFT Endpoint versions prior to 7.10.2 are affected by a path traversal vulnerability.

The Canadian Centre for Cyber Security issued advisory AV26-906 noting that Fortra GoAnywhere MFT Endpoint versions prior to 7.10.2 are affected by a path traversal vulnerability. The advisory was published September 10, 2026, referencing Fortra's own security advisory. No exploitation details or CVE id are provided; administrators are urged to review the links and apply the 7.10.2 update.

Canadian Centre for Cyber Security·Sep 10, 12:38 UTC · 5d agoAdvisory

HTTP/2 Bomb CVE-2026-49975

Fortinet advisory details CVE-2026-49975, an Apache HTTP Server HTTP/2 flaw enabling denial of service, affecting versions 2.4.17 through 2.4.67.

Fortinet PSIRT advisory FG-IR-26-163, revised 2026-08-19, covers CVE-2026-49975, a memory allocation with excessive size value flaw (HTTP/2 bomb) in Apache HTTP Server's mod_http2, scored CVSSv3 5.8. Malicious HTTP requests can cause a denial of service, and affected versions span Apache HTTP Server 2.4.17 through 2.4.67. The advisory text does not state which Fortinet product bundles the affected Apache component or whether exploitation has been observed.

Fortinet PSIRT·Aug 12, 07:00 UTC · Aug 12, 2026AdvisoryCVE-2026-49975

What the Fortibleed campaign means for organizations running FortiGate firewalls

Help Net Security·Aug 3, 13:19 UTC · Aug 3, 2026Threat actor

Hackers Exploit FortiGate SSL-VPN Flaw to Breach Thai ISP and Deploy MeshCentral Backdoor

Threat actors exploited FortiOS SSL-VPN flaw CVE-2024-21762 to breach Thai ISP Triple T Broadband, gaining root-level persistence via MeshCentral agents.

Attackers exploited CVE-2024-21762, an out-of-bounds write enabling unauthenticated RCE in FortiOS SSL-VPN, against Triple T Broadband's FortiGate 60F at mail.3bb.co.th, launching a Node.js reverse shell via a ROP payload. Hunt.io uncovered the operation through an exposed staging directory at 92.63.180[.]133:8888 containing 298 files of exploits, credential-harvesting scripts, session cookies, and a device inventory. Post-compromise, the actors deployed MeshCentral agents (device group TH-3BB, C2 www.ayuthayatech.com) running as root, plus a hidden SUID backdoor at /usr/local/bin/.rc, and also targeted an internal Pentaho/Tomcat server with Ghostcat (CVE-2020-1938). A cleanup script removed logs, shell histories, and web shells while deliberately preserving the MeshCentral agent and SUID backdoor.

GBHackers·Sep 15, 05:20 UTC · 1d agoExploit / PoC in the wild 3 sourcesCVE-2024-21762CVE-2020-1938