Security Digest · Vulnerability record
CVE-2025-59719: Fortinet FortiWeb vulnerability
An improper verification of cryptographic signature vulnerability in Fortinet FortiWeb 8.0.0, FortiWeb 7.6.0 through 7.6.4, FortiWeb 7.4.0 through 7.4.9 may allow an unauthenticated attacker to bypass the FortiCloud SSO login authentication via a crafted SAML response message.
CVSS 9.1 Critical EPSS 29.2% · p98 Act now
Should you act?
High exploit likelihood
EPSS ranks it in the top 5% of all CVEs for likely exploitation in the next 30 days. This signal is computed from CISA KEV, EPSS and CVSS data; it is not an editorial verdict.
- No confirmed exploitation. It is not in CISA’s KEV catalog and CISA’s SSVC assessment records no known exploitation. That can change quickly after a public write-up; re-check if you are affected.
- EPSS 29.2%, percentile 98: FIRST’s model estimates a 29.2% chance of exploitation activity in the next 30 days, higher than 98% of all scored CVEs (very high). EPSS is a probability, not a verdict.
- Remotely reachable with no login and no user interaction. If the vulnerable service is exposed to the internet, prioritize it.
- Editorial verdict: Act now. FortiCloud SSO SAML Bypass: CVE-2025-59718/59719 — If any Fortinet device has FortiCloud SSO admin login turned on, it was open to unauthenticated admin takeover; upgrade, then also apply the January 2026 fix for CVE-2026-24858, which bypassed this patch.
What it is
An improper verification of cryptographic signature vulnerability in Fortinet FortiWeb 8.0.0, FortiWeb 7.6.0 through 7.6.4, FortiWeb 7.4.0 through 7.4.9 may allow an unauthenticated attacker to bypass the FortiCloud SSO login authentication via a crafted SAML response message.
Weakness type: CWE-347.
Product: Fortinet FortiWeb · Assigned by: fortinet · Published: 2025-12-09
Affected and fixed versions
| Vendor | Product | Affected versions (per CVE record) |
|---|---|---|
| Fortinet | FortiWeb | 8.0.0, 7.6.0 <= 7.6.4, 7.4.0 <= 7.4.9 |
Severity scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| fortinet | 3.1 | 9.1 Critical | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:F/RL:O/RC:C |
- Attack vector: network (remotely reachable)
- Attack complexity: low
- Privileges required: none (no login)
- User interaction: none
- Scope: unchanged
CVSS measures how bad a flaw is if exploited, not how likely exploitation is. Read it next to the exploitation data below.
Exploitation and urgency
- CISA KEV: not listed (no confirmed in-the-wild exploitation known to CISA).
- CISA SSVC assessment: exploitation none, automatable yes, technical impact total.
- FIRST EPSS (model of 2026-10-21): 29.22% probability of exploitation activity in the next 30 days; percentile 98.
Timeline
- — CVE record published by fortinet
- — erroneo.us brief: FortiCloud SSO SAML Bypass: CVE-2025-59718/59719
- — CVE record last updated
Sources and references
Original sources first. Version and fix details should always be confirmed against the vendor or project advisory.
Vulnerability records
- CVE.org record CVE-2025-59719 cve.org
- NVD entry CVE-2025-59719 nvd.nist.gov
Other references from the CVE record and advisory
- fortiguard.fortinet.com fortiguard.fortinet.com
- cert-portal.siemens.com cert-portal.siemens.com