CVE-2026-24858: Fortinet Multiple Products Authentication Bypass Using an Alternate Path or Channel Vulnerability
- Is it exploited?
Yes. CISA added it to the Known Exploited Vulnerabilities catalog on , the same day the CVE record was published.
- How likely is exploitation in the next 30 days?
- 86.6%
EPSS score, percentile 99.7 of all scored records
- How severe?
- 9.4 Critical
CVSS v3.1 base score, given by the CNA
- What should I do?
CISA deadline . Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
The CVE record links no vendor advisory, patch or mitigation.
- Which versions are affected?
Affected
- 8.0.0 through 8.0.3
- 7.6.0 through 7.6.6
- 7.4.0 through 7.4.11
- 7.6.3 through 7.6.5
- 7.6.0 through 7.6.5
- 7.4.0 through 7.4.10
and 14 more in the table below
Source: CISA Known Exploited Vulnerabilities (KEV) catalog, 2026.10.28, as of ; FIRST Exploit Prediction Scoring System (EPSS), v2026.06.15, as of ; CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of . About the data.
What to do
Required action, set by CISA
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
CISA due date for this action: .
Solution (from the CVE record)
Upgrade to upcoming FortiOS version 8.0.0 or above Upgrade to FortiOS version 7.6.6 or above Upgrade to FortiOS version 7.4.11 or above Upgrade to FortiOS version 7.2.13 or above Upgrade to FortiOS version 7.0.19 or above Upgrade to upcoming FortiManager version 8.0.0 or above Upgrade to FortiManager version 7.6.6 or above Upgrade to FortiManager version 7.4.10 or above Upgrade to FortiManager version 7.2.12 or above Upgrade to FortiManager version 7.0.16 or above Upgrade to FortiAnalyzer version 7.6.6 or above Upgrade to FortiAnalyzer version 7.4.10 or above Upgrade to FortiAnalyzer version 7.2.12 or above Upgrade to FortiAnalyzer version 7.0.16 or above Upgrade to FortiProxy version 7.6.5 or above Upgrade to FortiProxy version 7.4.13 or above Upgrade to FortiProxy version 7.2.16 or above Upgrade to FortiProxy version 7.0.23 or above Upgrade to FortiWeb version 8.0.4 or above Upgrade to FortiWeb version 7.6.7 or above Upgrade to FortiWeb version 7.4.12 or above Upgrade to FortiNAC-F version 7.6.6 or above Upgrade to FortiSwitchManager version 7.2.9 or above Upgrade to FortiSwitchManager version 7.0.8 or above
Advisories and patches
The CVE record links no vendor advisory, patch or mitigation.
Linked from CISA's catalog entry
- https://fortiguard.fortinet.com/psirt/FG-IR-26-060
- https://www.fortinet.com/blog/psirt-blogs/analysis-of-sso-abuse-on-fortios
- https://nvd.nist.gov/vuln/detail/CVE-2026-24858
Affected products and versions
As listed in the CVE record.
| Status | Versions |
|---|---|
| Affected | 8.0.0 through 8.0.3 |
| Affected | 7.6.0 through 7.6.6 |
| Affected | 7.4.0 through 7.4.11 |
Versions not listed are: unaffected.
| Status | Versions |
|---|---|
| Affected | 7.6.3 through 7.6.5 |
Versions not listed are: unaffected.
| Status | Versions |
|---|---|
| Affected | 7.6.0 through 7.6.5 |
| Affected | 7.4.0 through 7.4.10 |
| Affected | 7.2.0 through 7.2.12 |
| Affected | 7.0.0 through 7.0.18 |
Versions not listed are: unaffected.
| Status | Versions |
|---|---|
| Affected | 7.6.0 through 7.6.5 |
| Affected | 7.4.0 through 7.4.9 |
| Affected | 7.2.0 through 7.2.11 |
| Affected | 7.0.0 through 7.0.15 |
Versions not listed are: unaffected.
| Status | Versions |
|---|---|
| Affected | 7.6.0 through 7.6.4 |
| Affected | 7.4.0 through 7.4.12 |
| Affected | 7.2.0 through 7.2.15 |
| Affected | 7.0.0 through 7.0.22 |
Versions not listed are: unaffected.
| Status | Versions |
|---|---|
| Affected | 7.6.0 through 7.6.5 |
| Affected | 7.4.0 through 7.4.9 |
| Affected | 7.2.0 through 7.2.11 |
| Affected | 7.0.0 through 7.0.15 |
Versions not listed are: unaffected.
Source: CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of . About the data.
About this vulnerability
Fortinet FortiAnalyzer, FortiManager, FortiOS, and FortiProxy contain an authentication bypass using an alternate path or channel that could allow an attacker with a FortiCloud account and a registered device to log into other devices registered to other accounts, if FortiCloud SSO authentication is enabled on those devices.
Summary: CISA's KEV catalog, as of .
- CISA added CVE-2026-24858 to its Known Exploited Vulnerabilities (KEV) catalog on 27 Jan 2026.
- CISA's ransomware flag for this entry is "Unknown": no evidence of ransomware use in the catalog, which is not proof of none.
- The due date CISA sets for the required action is 30 Jan 2026.
- The CVE record was published on 27 Jan 2026, the same day it was added to KEV.
- The CVE record carries a CVSS v3.1 base score of 9.4 (Critical), given by its CNA.
- FIRST's EPSS model puts the probability of exploitation in the next 30 days at 86.6% (percentile 99.7), as of 28 Oct 2026.
- CISA's SSVC assessment in the CVE record: exploitation active, automatable yes, technical impact total.
Source: CISA Known Exploited Vulnerabilities (KEV) catalog, 2026.10.28, as of ; CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of ; FIRST Exploit Prediction Scoring System (EPSS), v2026.06.15, as of . About the data.
Description
An Authentication Bypass Using an Alternate Path or Channel vulnerability [CWE-288] vulnerability in Fortinet FortiAnalyzer 7.6.0 through 7.6.5, FortiAnalyzer 7.4.0 through 7.4.9, FortiAnalyzer 7.2.0 through 7.2.11, FortiAnalyzer 7.0.0 through 7.0.15, FortiManager 7.6.0 through 7.6.5, FortiManager 7.4.0 through 7.4.9, FortiManager 7.2.0 through 7.2.11, FortiManager 7.0.0 through 7.0.15, FortiNAC-F 7.6.3 through 7.6.5, FortiOS 7.6.0 through 7.6.5, FortiOS 7.4.0 through 7.4.10, FortiOS 7.2.0 through 7.2.12, FortiOS 7.0.0 through 7.0.18, FortiProxy 7.6.0 through 7.6.4, FortiProxy 7.4.0 through 7.4.12, FortiProxy 7.2.0 through 7.2.15, FortiProxy 7.0.0 through 7.0.22, FortiWeb 8.0.0 through 8.0.3, FortiWeb 7.6.0 through 7.6.6, FortiWeb 7.4.0 through 7.4.11 may allow an attacker with a FortiCloud account and a registered device to log into other devices registered to other accounts, if FortiCloud SSO authentication is enabled on those devices.
Source: CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of . About the data.
Weakness
CWE and CAPEC are maintained by MITRE; the entries are those named in the CVE record and the KEV entry.
Timeline
| Date | Event |
|---|---|
| CVE record published | |
| Added to CISA KEV | |
| CISA due date for the required action | |
| CVE record last updated |
References
More exploited Fortinet vulnerabilities
- CVE-2025-61624: Fortinet Multiple Products Path Traversal Vulnerability
- CVE-2026-104286: Fortinet FortiMail Path Traversal Vulnerability
- CVE-2025-25249: Fortinet Multiple Products Heap-based Buffer Overflow Vulnerability
- CVE-2025-68686: Fortinet FortiOS Exposure of Sensitive Information to an Unauthorized Actor Vulnerability
- CVE-2026-25089: Fortinet FortiSandbox OS Command Injection Vulnerability
- CVE-2026-39808: Fortinet FortiSandbox OS Command Injection Vulnerability