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Vulnerability record · CVE-2025-53844 · published 12 May 2026

CVE-2025-53844: Fortinet fortios out-of-bounds write vulnerability

Fortinet · Fortios

A out-of-bounds write vulnerability in Fortinet FortiOS 7.6.0 through 7.6.3, FortiOS 7.4.0 through 7.4.8, FortiOS 7.2.0 through 7.2.11 allows attacker to execute unauthorized code or commands via specially crafted packets.

8.8 CVSS 3.1 High EPSS 0.56% · top 55.4% CWE-787 · Out-of-bounds write
8.8CVSS 3.1 base score
0.56%EPSS exploitation probability, 30 days
NoNot in CISA KEV
1Affected product versions listed by NVD
2References
17 Jun 2026Last modified by NVD

Description

A out-of-bounds write vulnerability in Fortinet FortiOS 7.6.0 through 7.6.3, FortiOS 7.4.0 through 7.4.8, FortiOS 7.2.0 through 7.2.11 allows attacker to execute unauthorized code or commands via specially crafted packets.

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Affected products

1 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

References

LinkTags
https://fortiguard.fortinet.com/psirt/FG-IR-26-123 Vendor Advisory
https://cert-portal.siemens.com/productcert/html/ssa-864900.html

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Related vulnerabilities

Same products first, then exploited flaws of the same weakness class.

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Source: NIST National Vulnerability Database (record CVE-2025-53844), CISA KEV, FIRST EPSS (scores of 2026-09-26). This page is refreshed as NVD updates the record.