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CVE-2025-53844 Fortinet CVE debrief

CVE-2025-53844 is an 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. This vulnerability allows an attacker to execute unauthorized code or commands via specially crafted packets. The CVSS score for this vulnerability is 8.8, indicating a high severity.

Vendor
Fortinet
Product
FortiOS
CVSS
HIGH 8.8
CISA KEV
Not listed in stored evidence
Original CVE published
2026-05-12
Original CVE updated
2026-06-09
Advisory published
2026-05-12
Advisory updated
2026-06-09

Who should care

Administrators and users of 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 should be aware of this vulnerability and take necessary actions to mitigate it.

Technical summary

The vulnerability is caused by an out-of-bounds write issue in Fortinet FortiOS. This allows an attacker to execute unauthorized code or commands via specially crafted packets.

Defensive priority

High

Recommended defensive actions

  • Apply patches or updates provided by Fortinet to fix the vulnerability.
  • Restrict access to affected systems and networks.
  • Monitor system logs for suspicious activity.

Evidence notes

The vulnerability is documented in the CVE record and NVD detail pages.

Official resources

CVE-2025-53844 was published on 2026-05-12T18:16:35.983Z and modified on 2026-06-09T10:16:38.300Z.