CVE-2024-55591: Fortinet FortiOS and FortiProxy Authentication Bypass 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?
- 94.4%
EPSS score, percentile 99.9 of all scored records
- How severe?
- 9.6 Critical
CVSS v3.1 base score, given by the CNA
- What should I do?
CISA deadline . Apply mitigations per vendor instructions 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
- 7.0.0 through 7.0.16
- 7.2.0 through 7.2.12
- 7.0.0 through 7.0.19
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 or discontinue use of the product if mitigations are unavailable.
CISA due date for this action: .
Solution (from the CVE record)
Upgrade to FortiOS version 7.0.17 or above Upgrade to FortiProxy version 7.2.13 or above Upgrade to FortiProxy version 7.0.20 or above
Advisories and patches
The CVE record links no vendor advisory, patch or mitigation.
Linked from CISA's catalog entry
Affected products and versions
As listed in the CVE record.
| Status | Versions |
|---|---|
| Affected | 7.0.0 through 7.0.16 |
Versions not listed are: unaffected.
| Status | Versions |
|---|---|
| Affected | 7.2.0 through 7.2.12 |
| Affected | 7.0.0 through 7.0.19 |
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 FortiOS and FortiProxy contain an authentication bypass vulnerability that may allow an unauthenticated, remote attacker to gain super-admin privileges via crafted requests to Node.js websocket module.
Summary: CISA's KEV catalog, as of .
- CISA added CVE-2024-55591 to its Known Exploited Vulnerabilities (KEV) catalog on 14 Jan 2025.
- CISA marks it as known to be used in ransomware campaigns.
- The due date CISA sets for the required action is 21 Jan 2025.
- The CVE record was published on 14 Jan 2025, the same day it was added to KEV.
- The CVE record carries a CVSS v3.1 base score of 9.6 (Critical), given by its CNA.
- FIRST's EPSS model puts the probability of exploitation in the next 30 days at 94.4% (percentile 99.9), 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] affecting FortiOS version 7.0.0 through 7.0.16 and FortiProxy version 7.0.0 through 7.0.19 and 7.2.0 through 7.2.12 allows a remote attacker to gain super-admin privileges via crafted requests to Node.js websocket module.
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
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