CVE-2025-25249
CriticalExploitedPublic exploitA 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…
Published Jan 13, 2026 · Updated Oct 15, 2026
Key Facts
Patch immediately- CVE-2025-25249 is a critical-severity vulnerability (CVSS 9.8 v3.1) affecting Fortisase (Fortinet), Fortiswitchmanager (Fortinet), Fortios (Fortinet) and 1 more product.
- It is exploited in the wild, listed in CISA KEV, Industry KEV feed, CIRCL KEV, ENISA EUVD since Sep 8, 2026. Public exploit code is available.
- EPSS estimates a 3.8% probability of exploitation in the next 30 days.
- Fixed versions are available, including Fortios 6.4.17, Fortios 7.0.18, Fortios 7.2.12.
- Brandefense priority: patch immediately, because it is listed as exploited in the wild.
CVSS v3.1
9.8
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS (30-day exploit likelihood)
3.8%
Higher than 89.8% of all scored CVEs
Exploited in the wild
Yes
4 catalog listings
Public exploit code
Available
Proof-of-concept or weaponized module
Get the full CVE-2025-25249 brief as a PDF
Every affected product and fixed release, exploitation status and a first 24 hours response checklist, emailed within minutes.
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
Known-Exploited Catalog Listings
| Catalog | Added | Remediation due | Ransomware use |
|---|---|---|---|
| CISA KEV | Sep 9, 2026 | Sep 12, 2026 | Not reported |
| Industry KEV feed | Sep 8, 2026 | Sep 12, 2026 | Not reported |
| CIRCL KEV | Sep 8, 2026 | Sep 12, 2026 | Not reported |
| ENISA EUVD | Sep 9, 2026 | n/a | Not reported |
Required action: Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.
Affected Products
28 affected entries in total| Product | Affected versions | Fixed in |
|---|---|---|
| FortisaseFortinet | 25.1.39, 25.1.51 | n/a |
| FortiswitchmanagerFortinet | 7.2.2, 7.2.3, 7.2.4, 7.2.5 | 7.0.6 |
| FortiosFortinet | 7.2.10, 7.2.11, 7.2.4, 7.2.5, 7.2.6, 7.2.7, 7.2.8, 7.2.9 | 6.4.17 |
| Ruggedcom Ape1808 FirmwareSiemens | See advisory | n/a |
Patched Releases
Fortios
6.4.17, 7.0.18, 7.2.12, 7.4.9, 7.6.4
Fortiswitchmanager
7.0.6, 7.2.7
Timeline
Publicly disclosed
Jan 13, 2026
Added to Industry KEV feed
Sep 8, 2026
Added to CIRCL KEV
Sep 8, 2026
Added to CISA KEV
Sep 9, 2026
Added to ENISA EUVD
Sep 9, 2026
Last updated
Oct 15, 2026
Weakness Type
- CWE-122 Heap-based Buffer Overflow
- CWE-787 Out-of-bounds Write
References
FAQ
Common Questions.
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 c…
Affected: Fortisase (Fortinet) versions 25.1.39, 25.1.51; Fortiswitchmanager (Fortinet) versions 7.2.2, 7.2.3, 7.2.4, 7.2.5; Fortios (Fortinet) versions 7.2.10, 7.2.11, 7.2.4, 7.2.5, 7.2.6, 7.2.7, 7.2.8, 7.2.9, among others. The full list is in the CVE brief.
It is exploited in the wild, listed in CISA KEV, Industry KEV feed, CIRCL KEV, ENISA EUVD since Sep 8, 2026.
Yes. It was added on Sep 9, 2026 with a federal remediation due date of Sep 12, 2026.
Public exploit code is available.
Fixed versions are available, including Fortios 6.4.17, Fortios 7.0.18, Fortios 7.2.12.
Brandefense priority: patch immediately, because it is listed as exploited in the wild.
Is CVE-2025-25249 Running On Your Attack Surface?
Brandefense maps vulnerabilities like this one to your internet-facing assets and tells you exactly where to patch.
Request A Demo