CVE-2024-21762: Fortinet FortiOS Out-of-Bound Write 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?
- 84.6%
EPSS score, percentile 99.7 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
- 7.4.0 through 7.4.2
- 7.2.0 through 7.2.6
- 7.0.0 through 7.0.13
- 6.4.0 through 6.4.14
- 6.2.0 through 6.2.15
- 6.0.0 through 6.0.18
and 9 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 or discontinue use of the product if mitigations are unavailable.
CISA due date for this action: .
Solution (from the CVE record)
Upgrade to FortiProxy version 7.4.3 or above Upgrade to FortiProxy version 7.2.9 or above Upgrade to FortiProxy version 7.0.15 or above Upgrade to FortiProxy version 2.0.14 or above Upgrade to FortiOS version 7.4.3 or above Upgrade to FortiOS version 7.2.7 or above Upgrade to FortiOS version 7.0.14 or above Upgrade to FortiOS version 6.4.15 or above Upgrade to FortiOS version 6.2.16 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 | 7.4.0 through 7.4.2 |
| Affected | 7.2.0 through 7.2.6 |
| Affected | 7.0.0 through 7.0.13 |
| Affected | 6.4.0 through 6.4.14 |
| Affected | 6.2.0 through 6.2.15 |
| Affected | 6.0.0 through 6.0.18 |
Versions not listed are: unaffected.
| Status | Versions |
|---|---|
| Affected | 7.4.0 through 7.4.2 |
| Affected | 7.2.0 through 7.2.8 |
| Affected | 7.0.0 through 7.0.14 |
| Affected | 2.0.0 through 2.0.13 |
| Affected | 1.2.1 through 1.2.13 |
| Affected | 01.02.00 |
| Affected | 1.1.4 through 1.1.6 |
| Affected | 01.01.00 through 01.01.03 |
| Affected | 01.00.00 through 01.00.07 |
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 contains an out-of-bound write vulnerability that allows a remote unauthenticated attacker to execute code or commands via specially crafted HTTP requests.
Summary: CISA's KEV catalog, as of .
- CISA added CVE-2024-21762 to its Known Exploited Vulnerabilities (KEV) catalog on 9 Feb 2024.
- CISA marks it as known to be used in ransomware campaigns.
- The due date CISA sets for the required action is 16 Feb 2024.
- The CVE record was published on 9 Feb 2024, 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 84.6% (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
A out-of-bounds write vulnerability in Fortinet FortiOS 7.4.0 through 7.4.2, FortiOS 7.2.0 through 7.2.6, FortiOS 7.0.0 through 7.0.13, FortiOS 6.4.0 through 6.4.14, FortiOS 6.2.0 through 6.2.15, FortiOS 6.0 all versions, FortiProxy 7.4.0 through 7.4.2, FortiProxy 7.2.0 through 7.2.8, FortiProxy 7.0.0 through 7.0.14, FortiProxy 2.0.0 through 2.0.13, FortiProxy 01.02 all versions, FortiProxy 1.2 all versions, FortiProxy 01.01 all versions, FortiProxy 1.1 all versions, FortiProxy 01.00 all versions allows attacker to execute unauthorized code or commands via specifically crafted requests
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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