Critical severity · published Jan 13, 2026
CVE-2025-25249
Fortinet Multiple Products Heap-based Buffer Overflow Vulnerability
In wildKEV
9.8
CVSS
3.7%
EPSS
Yes
On KEV
Description
A heap-based buffer overflow 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, FortiOS 7.0.0 through 7.0.17, FortiOS 6.4 all versions, FortiSwitchManager 7.2.0 through 7.2.6, FortiSwitchManager 7.0.0 through 7.0.5 allows attacker to execute unauthorized code or commands via specially crafted packets
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)3.7% · higher than 90% of CVEs
Exploited in the wildYes
CISA KEVListed Sep 9, 2026
Federal remediation dueSep 12, 2026
Ransomware campaign useNot known
Affected products
Which versions
FO
FortiOS · Fortinet
7.6.0 through 7.6.2; 7.4.0 through 7.4.7; 7.2.4 through 7.2.11 · source: vendor, NVD
FO
FortiSwitchManager · Fortinet
7.2.2 through 7.2.5 · source: vendor, NVD
FO
Fortisase · Fortinet
25.1.39; 25.1.51 · source: NVD
RA
Ruggedcom Ape1808 Firmware · Siemens
All versions, or not specified · source: NVD
RA
MP
Multiple Products · Fortinet
All versions, or not specified · source: KEV
In the news
AdvisoryHigh
CISA Adds Four Known Exploited Vulnerabilities to Catalog
CISA has added four new vulnerabilities to its Known Exploited Vulnerabilities (KEV) Catalog , based on evidence of active exploitation.   CVE-2025-25249 Fortinet Multiple Products Heap-based Buffer Overflow Vulnerability CVE-2026-19490 Citrix NetScaler Authentication Bypass Using an Alternate Path or Channel Vulnerability CVE-2026-87491 Google Chromium V8 Out of Bounds Write Vulnerability CVE-2026-20079 Cisco Firewall Management Center Authentication Bypass Using an Alternate Path or Channel Vulnerability  These types of vulnerabilities are a frequent attack vector for malicious cyber actors and pose significant risks to the federal enterprise. Binding Operational Directive (BOD) 26-04: Prioritizing Security Updates Based on Risk establishes vulnerability management requirements for Federal Civilian Executive Branch (FCEB) agencies. BOD 26-04 reinforces the importance of the KEV Catalog and requires federal agencies to prioritize rapid remediation of high-risk vulnerabilities, specifically those identified by Common Vulnerabilities and Exposures (CVEs) listed in CISA’s KEV Catalog on publicly exposed assets that grant total control of the asset post-exploitation, while deferring action for lower-risk vulnerabilities. BOD 26-04 further establishes basic expectations for when agencies must check whether threat actors compromised the system before the patch was applied. While BOD 26-04 applies only to FCEB agencies, CISA encourages all org...
Sep 9, 2026·CISA Advisories
Affected product
FO
FortiOS
Fortinet
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