---
title: "CVE-2025-25249: Fortinet Multiple Products Heap-based Buffer Overflow Vulnerability"
url: https://erroneo.us/security/cve/CVE-2025-25249/
description: "CVE-2025-25249 (Fortinet Multiple Products): Exploited in the wild (CISA KEV). A heap-based buffer overflow vulnerability in Fortinet FortiOS 7.6.0 through…"
type: vulnerability-record
section: "Security Digest"
date_published: 2026-01-13
date_modified: 2026-10-16
publisher: erroneo.us
author: erroneo.us Security Desk
cve: "CVE-2025-25249"
kev: true
cvss: 7.4
epss: 0.03802
license: All rights reserved. Quote with attribution and a link.
---

# CVE-2025-25249: Fortinet Multiple Products Heap-based Buffer Overflow Vulnerability

**Signal:** Exploited: patch now if you run it. CISA has confirmed exploitation in the wild. (Computed from CISA KEV, EPSS and CVSS; not an editorial verdict.)

## Should you act?

- Yes, if you run Fortinet Multiple Products. CISA added this CVE to its Known Exploited Vulnerabilities catalog on 2026-09-09, which means there is reliable evidence of exploitation in the wild. US federal agencies must remediate by 2026-09-12 ; treat that as the outer limit, not the target.
- EPSS 3.8% , percentile 90: FIRST’s model estimates a 3.8% chance of exploitation activity in the next 30 days, higher than 90% of all scored CVEs (elevated). EPSS is a probability, not a verdict.
- Remotely reachable with no login and no user interaction. If the vulnerable service is exposed to the internet, prioritize it.
- Editorial verdict: Act now. FortiOS CVE-2025-25249 and CVE-2025-61624 Now Exploited — If you run FortiGates, get to FortiOS 7.4.10+ or 7.6.5+ now and hunt for implants: one bug gives unauthenticated attackers code execution over CAPWAP and is being exploited at scale, and the other turns stolen admin logins into root implants.

## What it is

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

## Affected products (CVE record)

- Fortinet FortiSwitchManager: 7.2.2 <= 7.2.5
- Fortinet FortiOS: 7.6.0 <= 7.6.2, 7.4.0 <= 7.4.7, 7.2.4 <= 7.2.11

## Severity

- fortinet CVSS 3.1: 7.4 `CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H/E:P/RL:W/RC:C`

## Exploitation

- CISA KEV: added 2026-09-09; federal due date 2026-09-12. Known ransomware use: Unknown.
- CISA 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.
- CISA SSVC assessment: exploitation active , automatable no , technical impact total .
- FIRST EPSS (model of 2026-10-21): 3.80% probability of exploitation activity in the next 30 days; percentile 90.

## Sources

- [Listed in CISA KEV notes (fortiguard.fortinet.com)](https://fortiguard.fortinet.com/psirt/FG-IR-25-084)
- [CVE.org record CVE-2025-25249](https://www.cve.org/CVERecord?id=CVE-2025-25249)
- [NVD entry CVE-2025-25249](https://nvd.nist.gov/vuln/detail/CVE-2025-25249)
- [CISA Known Exploited Vulnerabilities catalog entry](https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2025-25249)
- [Listed in CISA KEV notes (cisa.gov)](https://www.cisa.gov/news-events/directives/bod-26-04-prioritizing-security-updates-based-risk)
- [Listed in CISA KEV notes (cisa.gov)](https://www.cisa.gov/news-events/directives/bod-26-04-implementation-guidance-prioritizing-security-updates-based-risk)
- [socradar.io](https://socradar.io/blog/cve-2025-25249-pivotc2-fortigate-rat/)
- [cert-portal.siemens.com](https://cert-portal.siemens.com/productcert/html/ssa-864900.html)

---
Source page: https://erroneo.us/security/cve/CVE-2025-25249/ · Security Digest: https://erroneo.us/security/ · More: https://erroneo.us/llms.txt