Fortinet Auth Bypass Attacks: Detect Faster With AI

Most companies get the order of operations wrong during a perimeter-device emergency. They argue about patch windows first—and only later ask the uncomfortable question: “Are we already compromised?”

This week’s Fortinet situation makes that mistake expensive. Two critical authentication bypass vulnerabilities in Fortinet platforms (CVE-2025-59718 and CVE-2025-59719, both CVSS 9.1) are being exploited in the wild. The pattern reported by defenders is blunt: attackers target admin access, get in via malicious SSO logins, then export device configurations—including hashed credentials and network-sensitive details.

If you run FortiOS/FortiWeb/FortiProxy/FortiSwitchManager in production, the lesson isn’t just “patch quickly.” It’s that AI-assisted detection and response can shrink the gap between disclosure and containment—especially when attackers begin probing within days.

What’s actually happening in these Fortinet attacks

Answer first: Attackers are bypassing SSO authentication (when FortiCloud SSO is enabled) using crafted SAML messages, then abusing admin-level access to exfiltrate configurations and credential material.

These vulnerabilities affect the authentication layer in a way that’s tailor-made for perimeter compromise:

• The bypass hinges on improper verification of cryptographic signatures in SAML flows.
• When successful, the attacker doesn’t need valid credentials to obtain privileged access.
• After access, the attacker can export configurations, capturing details that enable follow-on intrusion.

Why that’s so dangerous: a firewall or gateway isn’t “just another server.” It’s the device that sees—and can change—traffic policy, VPN access, routing behavior, and inspection rules. If an attacker can alter those controls, they can turn your security boundary into a forwarding service for their next steps.

The “quiet exfil” phase is the real tell

A lot of teams look for obvious disruption: a service crash, a DDoS, a sudden outage. But the reported behavior here is subtler and arguably more damaging:

• Malicious SSO login
• Admin access achieved
• Configuration export to attacker-controlled infrastructure

That exported config often becomes a blueprint of your environment: interface layout, VPN parameters, trusted networks, admin users, and hashed secrets. Even if passwords are hashed, attackers can crack weak ones offline.

The trap: FortiCloud SSO “wasn’t enabled”… until it was

Answer first: Some devices may be more exposed than teams think because FortiCloud SSO can become enabled during registration unless explicitly disabled.

Here’s the operational pitfall: many organizations assume factory defaults reflect current production reality. In practice, features can get enabled by workflows—especially GUI registration flows—without anyone thinking of it as a security posture change.

The takeaway I want you to internalize is simple:

Your risk isn’t defined by the vendor default; it’s defined by what your environment drifted into over time.

This is where AI in cybersecurity earns its keep: config drift detection and policy change monitoring are ideal machine-learning problems because the system can learn what “normal for your fleet” looks like and flag deviations quickly.

Why “patch faster” isn’t enough (and what to do in the first hour)

Answer first: During active exploitation of perimeter flaws, the fastest risk reduction comes from reducing exposure of management interfaces and disabling the vulnerable auth path—then validating compromise—then patching.

Patching is mandatory. But patching takes time: change control, maintenance windows, regression concerns, HA failovers, remote sites. Meanwhile, the attacker’s timeline is measured in minutes.

Here’s a practical order-of-operations that works under pressure.

Step 1: Contain exposure immediately

Do these before your patch window if you can’t patch right away:

1. Disable FortiCloud administrative login if you use it (or disable the FortiCloud SSO path tied to admin auth) until patched.
2. Restrict management access (http/https admin, SSH) to trusted IP ranges only.
3. If possible, move management to a dedicated management network or behind a jump host.
4. Confirm you are not exposing management interfaces broadly to the Internet.

These are “boring” controls. They’re also the controls that stop mass exploitation.

Step 2: Assume credential exposure if indicators appear

If you see suspicious admin logins or unexpected configuration exports, treat it like credential theft. Response actions should include:

• Resetting firewall and administrative credentials
• Rotating secrets stored on or used by the appliance (where applicable)
• Invalidating sessions and reviewing admin accounts for rogue additions

Step 3: Patch, but verify you patched the right fleet

Fortinet released fixes across product lines. For FortiOS, patched versions include 7.6.4, 7.4.9, 7.2.12, and 7.0.18 or higher.

The operational gotcha: enterprises rarely have one version. They have many. филиals, acquisitions, lab appliances, DR sites. Your exposure is defined by the oldest, forgotten edge box.

This is where AI-driven asset intelligence helps: an automated system can continuously reconcile:

• what you think you have (CMDB)
• what is actually reachable and running
• what is currently vulnerable

Where AI helps: earlier detection, faster triage, fewer blind spots

Answer first: AI improves outcomes in active exploitation by correlating weak signals (auth anomalies, config exports, odd admin behavior) and automating the first-response playbook at machine speed.

Security teams don’t lose because they’re unskilled. They lose because they’re overloaded, and modern attacks create more data than humans can reliably interpret fast enough.

Below are the highest ROI AI use cases for this exact class of incident.

AI use case #1: Anomaly detection on admin authentication

When exploitation starts with authentication bypass, your best early warning is often behavioral:

• Admin logins at unusual times
• Logins from hosting providers or uncommon geographies
• Sudden “first seen” IPs hitting SSO endpoints
• Short bursts of attempts across many devices

A good model doesn’t need to “know it’s CVE-2025-59718.” It just needs to know: this admin auth pattern doesn’t match your baseline.

What I’ve found effective in practice is scoring anomalies across multiple dimensions (IP reputation, ASN, time-of-day, endpoint path, device role) and triggering an automated containment workflow when a threshold is crossed.

AI use case #2: Detecting configuration export behavior

The reported activity includes exporting device configurations. That’s a gift to defenders—if you’re watching for it.

AI-backed detection can:

• Flag rare administrative actions (config export, backup download, bulk policy export)
• Correlate the action to a suspicious login chain
• Alert with context: device name, admin account, source IP, destination, time sequence

This matters because it turns a generic alert into an actionable one.

AI use case #3: Automated “KEV-style” patch prioritization

CISA placing a vulnerability into a known exploited list is basically a signal flare: exploitability is not theoretical.

AI-driven vulnerability management can:

• Auto-tag assets exposed to Internet-facing management
• Prioritize patches based on exposure + exploit status + business criticality
• Recommend interim mitigations when patching is delayed

It’s the difference between “patch everything eventually” and “patch what attackers can hit today.”

AI use case #4: Continuous validation (post-patch confidence)

Patching doesn’t prove you’re safe; it proves you changed code.

After patching, you still need to know whether the device was used as an access point. AI-assisted monitoring helps by continuously looking for compromise indicators like:

• New or unauthorized admin accounts
• Unexpected jsconsole sessions
• Unusual SSL VPN authentication events
• Policy changes outside approved change windows

The best teams treat this as continuous validation, not a one-time incident task.

A practical checklist for security leaders (what I’d ask for by end of day)

Answer first: The goal is to reduce exposure, validate compromise, and accelerate remediation—without waiting for perfect information.

If you’re a CISO, IT director, or security ops lead, here’s a concrete checklist you can assign immediately:

1. Inventory Fortinet devices and versions (including remote sites and DR).
2. Confirm FortiCloud SSO status and disable it where not required.
3. Lock down management access to trusted IPs and remove broad Internet exposure.
4. Hunt for:
   • suspicious admin logins
   • config export events
   • new admin users
   • unexplained policy/VPN changes
5. Rotate credentials if suspicious activity is found (don’t debate it for days).
6. Patch to fixed versions and verify success (don’t rely on “job completed”).
7. Implement AI-backed monitoring for admin behavior and configuration actions on perimeter gear.

If you can’t do all seven today, do #2 and #3 first. They reduce blast radius fastest.

The bigger pattern in the “AI in Cybersecurity” series

Answer first: Perimeter-device exploits keep winning because they’re scalable for attackers and operationally hard for defenders; AI reduces that advantage by compressing detection and response time.

This Fortinet event fits an increasingly common pattern: disclosure, rapid exploitation, configuration theft, and follow-on access. It’s the same reason attackers love VPN gateways, firewalls, and identity plumbing—they’re high-impact and centrally positioned.

AI doesn’t replace patching discipline or good network design. It does something equally valuable: it buys time. It detects weak signals early, helps triage what matters, and automates the first moves that stop opportunistic exploitation.

If you’re thinking about where AI belongs in your security program in 2026, start here: Internet-facing identity and management paths. They’re where minutes matter and where automation pays for itself.

What would your team see—and how fast would it respond—if a compromised admin session exported your firewall config at 2:13 a.m. on a Friday night?