# CVE-2025-58903 — Fortinet FortiOS

> As of 2026-09-13, CVE-2025-58903 is a LOW-severity vulnerability in Fortinet FortiOS, CVSS v3.1 2.5, EPSS 0.6% (48.2th percentile). Threadlinqs Intelligence links 1 tracked threat campaign to CVE-2025-58903, most recently “Multiple Vulnerabilities in Fortigate NGFW on RUGGEDCOM APE1808 Devices (SSA-864900) — Including Actively Exploited FortiCloud SSO Bypass (CVE-2025-59718/-59719) and FortiOS Heap Overflow (CVE-2025-25249)”.

**Last updated:** 2026-08-11

## What is CVE-2025-58903?

An Unchecked Return Value vulnerability [CWE-252] in Fortinet FortiOS version 7.6.0 through 7.6.3 and before 7.4.8 API allows an authenticated user to cause a Null Pointer Dereference, crashing the http daemon via a specialy crafted request.

The record classifies CVE-2025-58903 under weakness class [CWE-252](https://cwe.mitre.org/data/definitions/252.html). Its CVSS v3 base vector states that the flaw is reachable remotely over the network, needs high-privilege credentials, needs no user interaction. 1 affected-product entry is recorded, across 1 vendor, listed below. The identifier was first published 388 days ago.

## Severity and exploitation probability

- **CVSS v3.1 base score:** 2.5 — LOW (`CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:L/E:P/RL:O/RC:C`)
- **EPSS (FIRST):** 0.6% probability of exploitation in the next 30 days, higher than 48.2% of all scored CVEs
- **CISA KEV:** Not listed in the CISA Known Exploited Vulnerabilities catalog
- **Threadlinqs priority:** 3.2/10 — a Threadlinqs composite of the CVSS base score, the EPSS percentile and public exploit availability
- **Published:** 2025-10-14, last modified 2026-08-11

## Is CVE-2025-58903 being exploited?

It currently carries a trending score of 17 in the Threadlinqs vulnerability feed.

## Affected products and versions

- [Fortinet](https://intel.threadlinqs.com/vendors/fortinet): FortiOS

## How to fix CVE-2025-58903

No vendor patch reference has been recorded for CVE-2025-58903 in the tracked sources. Follow the references below for a fix, and treat the products listed above as exposed until the vendor states otherwise.

## Threat activity tracking CVE-2025-58903

1 tracked threat in the Threadlinqs corpus references CVE-2025-58903, either in the campaign’s CVE list or as an indicator on the campaign record.

- [Multiple Vulnerabilities in Fortigate NGFW on RUGGEDCOM APE1808 Devices (SSA-864900) — Including Actively Exploited FortiCloud SSO Bypass (CVE-2025-59718/-59719) and FortiOS Heap Overflow (CVE-2025-25249)](https://intel.threadlinqs.com/threat/TL-2026-2486) — CRITICAL · 2026-09-13

## Sources

Enriched from CVE.org, FIRST EPSS. Last verified by Threadlinqs on 2026-10-10.

**Other references**

- [fortiguard.fortinet.com](https://fortiguard.fortinet.com/psirt/FG-IR-25-653)

Canonical: https://intel.threadlinqs.com/cve/CVE-2025-58903
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