Out-of-Bounds Write in Fortinet FortiWeb Enables Code Execution

Publication date: 2026-04-14

Last updated on: 2026-04-20

Assigner: Fortinet, Inc.

Description

An out-of-bounds write vulnerability [CWE-787] vulnerability in Fortinet FortiWeb 8.0.0 through 8.0.3, FortiWeb 7.6.0 through 7.6.6, FortiWeb 7.4.0 through 7.4.11 may allow a remote privileged attacker to execute arbitrary code or command via crafted HTTP requests.

CVSS Scores

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Meta Information

Published

2026-04-14

Last Modified

2026-04-20

Generated

2026-07-06

AI Q&A

2026-04-15

EPSS Evaluated

2026-07-05

NVD

CVE-2026-40688

EUVD

EUVD-2026-22808

Affected Vendors & Products

Vendor	Product	Version / Range
fortinet	fortiweb	From 7.6.0 (inc) to 7.6.7 (exc)
fortinet	fortiweb	From 8.0.0 (inc) to 8.0.4 (exc)
fortinet	fortiweb	From 7.4.0 (inc) to 7.4.12 (exc)

Helpful Resources

Exploitability

CWE

KEV

CWE ID	Description
CWE-787	The product writes data past the end, or before the beginning, of the intended buffer.

Attack-Flow Graph

Executive Summary

This vulnerability is an out-of-bounds write issue found in Fortinet FortiWeb versions 7.4.0 through 7.4.11, 7.6.0 through 7.6.6, and 8.0.0 through 8.0.3. It may allow an attacker to execute unauthorized code or commands on the affected system.

Impact Analysis

The vulnerability can lead to unauthorized code or command execution, which may compromise the confidentiality, integrity, and availability of the affected system.

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