Fortinet security advisory (AV26-898)
Canadian Cyber Centre advisory AV26-898 flags Fortinet vulnerabilities across FortiOS, FortiProxy, FortiPAM, FortiSandbox and FortiMonitorOnSight, urging administrators to apply updates
The Canadian Centre for Cyber Security relayed Fortinet PSIRT advisories (AV26-898) listing vulnerabilities affecting FortiOS 7.6.1-7.6.6, FortiProxy 7.6.2-7.6.6, FortiPAM Chrome extensions 7.4/8.0, FortiSandbox 4.4 and 5.0, FortiSandbox Cloud and PaaS 5.0.4-5.0.5, and FortiMonitorOnSight 7.2. The bulletin does not detail individual CVEs or exploitation. Administrators and users are encouraged to review the linked Fortinet advisories and apply the necessary updates.
ZDI-26-645: Fortinet FortiSandbox write_remote_backup_to_crontab cronValue Command Injection Remote Code Execution Vulnerability
ZDI publishes ZDI-26-645 for CVE-2026-84387, an authenticated command injection RCE in Fortinet FortiSandbox via crontab backup, rated CVSS 7.2.
Zero Day Initiative published advisory ZDI-26-645 describing a command injection flaw in Fortinet FortiSandbox's write_remote_backup_to_crontab function. Remote authenticated attackers can execute arbitrary code through the cronValue parameter. ZDI rated the issue CVSS 7.2 and assigned CVE-2026-84387.
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.
Open Redirect on FortiSIEM
Fortinet disclosed an open redirect flaw (CVSS 2.8) in FortiSIEM allowing authenticated attackers to redirect users to arbitrary websites via crafted HTTP requests.
Fortinet advisory FG-IR-26-169 covers an open redirect vulnerability (CWE-601) in FortiSIEM, rated CVSSv3 2.8. An authenticated attacker can cause a redirection to any website via specially crafted HTTP requests. The advisory was revised on 2026-09-08.
JWT used for authentication in web GUI signed with static key
Fortinet warns that FortiMonitorOnSight's web GUI uses JWTs signed with a static key, enabling remote unauthenticated authentication bypass.
Fortinet advisory FG-IR-26-170 discloses a CVSS 9.6 vulnerability (CWE-540, sensitive information in source code) in the FortiMonitorOnSight web portal. The web GUI's JWT authentication tokens are signed with a static key, allowing a remote unauthenticated attacker to bypass authentication via forged or reused JWTs. The advisory was revised on September 8, 2026.
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.
Broken Access control on Websocket streams
Fortinet FortiSOAR access control flaw (CVSS 4.9) lets zero-permission authenticated attackers subscribe to and inject broadcast messages into websocket streams.
Fortinet advisory FG-IR-26-164 discloses an improper access control vulnerability (CWE-284, CVSSv3 4.9) in FortiSOAR. An authenticated attacker with zero permissions can subscribe to websocket streams and topics and inject broadcast messages via crafted websocket requests. The advisory was revised on 2026-09-08.
Cron Job Injection in Remote Backup
Fortinet FortiSandbox command injection flaw (CVSS 6.7) in remote backup cron jobs lets privileged attackers execute arbitrary code via crafted HTTP requests.
Fortinet advisory FG-IR-26-167 discloses a command injection vulnerability (CWE-77, CVSSv3 6.7) in FortiSandbox's remote backup cron job functionality. A privileged attacker can execute unauthorized code or commands via crafted HTTP requests. The advisory was revised on 2026-09-08.
Null Pointer Dereference in Log Report
Fortinet patched a low-severity null pointer dereference (CVSS 2.5) in FortiOS, FortiProxy, and FortiPAM that lets authenticated attackers crash the httpsd daemon.
Fortinet advisory FG-IR-26-173 describes a NULL pointer dereference vulnerability (CWE-476) in FortiOS, FortiProxy, and FortiPAM, scored CVSSv3 2.5. An authenticated attacker can crash the httpsd daemon via crafted HTTP requests, causing a denial of service. The advisory was revised on 2026-09-08.
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.
Unauthenticated Control of NAT Rules Leading to Exposure of Sensitive Information
Fortinet fixed an improper access control flaw (CVSS 8.9) in FortiSandbox, FortiSandbox Cloud, and FortiSandbox PaaS letting unauthenticated attackers access sensitive information.
Fortinet advisory FG-IR-26-166 discloses an improper access control vulnerability (CWE-284) in the FortiSandbox, FortiSandbox Cloud, and FortiSandbox PaaS web UI, rated CVSSv3 8.9. The advisory title indicates unauthenticated control of NAT rules leading to exposure of sensitive information. An unauthenticated attacker can access sensitive data via crafted HTTP requests. The advisory was revised on 2026-09-08.
ZTNA Portal Improper Certificate Validation
Fortinet fixed an improper certificate validation flaw (CVSS 7.3) in FortiOS and FortiProxy Agentless ZTNA portal enabling unauthenticated man-in-the-middle attacks on backend traffic.
Fortinet advisory FG-IR-26-174 discloses an improper certificate validation vulnerability (CWE-295) in the FortiOS and FortiProxy Agentless ZTNA portal, rated CVSSv3 7.3. A remote and unauthenticated attacker can perform a man-in-the-middle attack on the communication channel between the ZTNA portal and the backend destination website. The advisory was revised on 2026-09-08.
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.
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.
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.
Oracle Patches 800+ Vulnerabilities in September 2026 Security Update
Oracle's September 2026 Critical Patch Update fixes 800+ vulnerabilities, including over 100 critical flaws and 240+ remotely exploitable without authentication.
Oracle released 673 new security patches in its September 2026 Critical Security Patch Update, resolving 672 unique CVEs across 17 risk matrices plus 130+ additional CVEs. More than 100 flaws are critical severity and over 240 are remotely exploitable without authentication. Oracle E-Business Suite received the largest batch with 159 patches, followed by Fusion Middleware (153, including 78 unauthenticated remote flaws) and Hyperion (102). Oracle reports no exploitation of these specific flaws but warns attackers routinely exploit unpatched Oracle products.
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.