Cyber Resilience

CVE-2024-26006

XSS in Fortinet Fortios 6.4.0 – 7.0.14

Published
14 March 2025
Modified
24 July 2025
Patch / advisory
CVSS Score v3.1 7.5
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H
EPSS Score 0.0059 45th percentile
Risk Priority 57 floored blend · peak EPSS

Summary

CVE-2024-26006 is a high-severity Cross-site Scripting (CWE-79) vulnerability in Fortinet Fortios. Its CVSS base score is 7.5 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Browser Session Hijacking (T1185); ranked at the 45th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

The strongest mitigations our analysis identified map to SA-11 (Developer Testing and Evaluation) and SI-10 (Information Input Validation) — see the control section below for these in your framework.

Deeper analysis AI-assisted summary

Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.

CVE-2024-26006 is an improper neutralization of input during web page generation vulnerability (CWE-79), enabling cross-site scripting (XSS) in the web SSL VPN UI of FortiOS versions 7.4.3 and below, 7.2.7 and below, and 7.0.13 and below, as well as FortiProxy versions 7.4.3 and below, 7.2.9 and below, and 7.0.16 and below. Published on 2025-03-14, it carries a CVSS v3.1 base score of 7.5 (AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H).

A remote unauthenticated attacker can exploit this vulnerability by leveraging a malicious Samba server to inject scripts into the SSL VPN web UI. Exploitation requires high attack complexity and user interaction, such as a victim accessing the VPN portal in a way that triggers interaction with the attacker's controlled Samba server, potentially leading to high-impact confidentiality, integrity, and availability consequences within the user's browser context.

Fortinet's advisory at https://fortiguard.fortinet.com/psirt/FG-IR-23-485 provides details on affected versions and mitigation recommendations. Security practitioners should consult this reference for patching instructions and workarounds.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

An improper neutralization of input during web page Generation vulnerability [CWE-79] in FortiOS version 7.4.3 and below, version 7.2.7 and below, version 7.0.13 and below and FortiProxy version 7.4.3 and below, version 7.2.9 and below, version 7.0.16 and below web…

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SSL VPN UI may allow a remote unauthenticated attacker to perform a Cross-Site Scripting attack via a malicious samba server.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise Techniques

T1185 Browser Session Hijacking Collection
Adversaries may take advantage of security vulnerabilities and inherent functionality in browser software to change content, modify user-behaviors, and intercept information as part of various browser session hijacking techniques.
T1539 Steal Web Session Cookie Credential Access
An adversary may steal web application or service session cookies and use them to gain access to web applications or Internet services as an authenticated user without needing credentials.
T1659 Content Injection Initial Access
Adversaries may gain access and continuously communicate with victims by injecting malicious content into systems through online network traffic.
T1189 Drive-by Compromise Initial Access
Adversaries may gain access to a system through a user visiting a website over the normal course of browsing.
T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2023-29183Same product: Fortinet Fortios
CVE-2023-36555Same product: Fortinet Fortios
CVE-2023-22638Same vendor: Fortinet
CVE-2023-0010Same product class: VPN / SSL gateway
CVE-2023-6789Same product class: VPN / SSL gateway
CVE-2023-41843Same vendor: Fortinet
CVE-2023-41844Same vendor: Fortinet
CVE-2023-41681Same vendor: Fortinet
CVE-2023-41836Same vendor: Fortinet
CVE-2023-6790Same product class: VPN / SSL gateway

Affected Assets

fortinet
fortios
6.4.0 — 7.0.14 · 7.2.0 — 7.2.8 · 7.4.0 — 7.4.4
fortinet
fortiproxy
7.0.0 — 7.0.17 · 7.2.0 — 7.2.10 · 7.4.0 — 7.4.4

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

Detect
Catch it (NIST detect / respond)

Harden
Shrink the surface (DISA STIG)

Validate
Prove the fix (OWASP ASVS)
  • V1.1.2
  • V1.3.2

Mitigating Controls (NIST 800-53 r5) AI

Developer testing and evaluation can discover missing or incorrect input neutralization through targeted web-application tests.

Input validation directly enforces neutralization of untrusted data before it reaches web output generation.

Output filtering can catch or sanitize unneutralized script content before it is served to users.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.PS-06 mostly match
prevents

Secure SDLC practices directly target introduction of XSS via coding standards/testing (mostly), yet the single broad outcome leaves many specific neutralization vectors unaddressed (partial).

PR.PS-02 partial match
prevents

Patching and EOL replacement can remediate known XSS instances in libraries or frameworks (partial) but do nothing to enforce input neutralization in application code (none).

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

finds

Secure-coding testing and automated code-analysis tools are applied to detect improper neutralization of script-related content during web-page generation.

prevents

Knowledge exchange on emerging attack techniques and patches reduces the likelihood that cross-site scripting flaws remain unaddressed in deployed applications.

prevents

Operational indicators of compromise for web-application attacks can be incorporated into WAF or input-filtering rules, lowering the likelihood that unsanitized data reaches the browser.

prevents

Requiring language-specific secure-coding standards and automated scanning during the SDLC catches missing output encoding or improper neutralization of untrusted data before the software reaches production.

prevents

Secure-coding standards, SAST scans and removal of insecure code samples together eliminate the failure to neutralize script content that produces cross-site scripting flaws.

none

Webpage malware scanning and block-listing of known malicious sites reduce the likelihood that reflected or stored script payloads reach a user’s browser.

References