Skip to content
Fencer Vulns
critical 9.8

CVE-2024-55591 kev+ ransomware in the critical feed json

An Authentication Bypass Using an Alternate Path or Channel vulnerability [CWE-288] affecting FortiOS version 7.0.0 through 7.0.16 and Fort…

published 2025-01-14 21 mo ago modified 2026-08-05 3 mo ago also EUVD-2024-52819

cvss
9.8
version 3.1, CNA
cisa kev
Exploited
added 2025-01-14, used in ransomware
epss
94.3%
EPSS 94.3% chance of exploitation in 30 days, percentile 99.8%
public exploits
0
none known, plus a Nuclei check

Summary

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.

Patch / fix

cisa required action Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.

  • fortinet fortiproxy 7.0.20, 7.2.13
  • fortinet fortios 7.0.17

Timeline

  1. Added to CISA KEV
  2. Published
  3. CISA patch deadline
  4. CISA SSVC: exploitation active

Known exploited

Added
21 mo ago
Patch by
2025-01-21 (21 mo ago)
Ransomware
Known to be used in ransomware campaigns
Required action
Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.
Vendor, product
Fortinet, FortiOS and FortiProxy
CISA name
Fortinet FortiOS and FortiProxy Authentication Bypass Vulnerability

Ransomware

Groups reported to have exploited it in intrusions.

  • Hunters International ransomware gang
  • SuperBlack ransomware gang
  • NightSpire ransomware gang
  • TheGentlemen ransomware gang
  • DragonForce ransomware gang
  • Qilin ransomware gang

reported by esentire.comforescout.coms-rminform.comresearch.checkpoint.comccb.belgium.becheckpoint.com

Ransomware Vulnerability Matrix by BushidoUK (github.com/BushidoUK/Ransomware-Vulnerability-Matrix), reformatted per CVE. CC BY 4.0

ATT&CK techniques

How it is exploited and what it leads to, in MITRE ATT&CK terms.

  • T1068 Exploitation for Privilege Escalation exploitation
  • T1078 Valid Accounts primary impact
  • T1555 Credentials from Password Stores primary impact
  • T1021 Remote Services secondary impact

kev release 2025-07-28, att&ck v16.1. KEV to ATT&CK mappings by the MITRE Center for Threat-Informed Defense (Mappings Explorer, Apache-2.0). © 2026 The MITRE Corporation. This work is reproduced and distributed with the permission of The MITRE Corporation. Terms of use

CISA SSVC

Exploitation
Active, exploited in the wild
Automatable
yes
Technical impact
total
Assessed
21 mo ago

Exploit prediction

94.35% chance of exploitation in the next 30 days, higher than 99.8% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

CVSS scores

assigned by version score vector
CNA 3.1 9.6 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:H/RL:O/RC:C
CNA 3.1 9.8 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
NVD 3.1 9.8 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Affected products

  • Fortinet FortiOS
  • Fortinet FortiProxy

Classification

Weakness
  • CWE-288 Authentication Bypass Using an Alternate Path or Channel
Technology feeds

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.