No exploitation reportedFix available

CVE-2026-40688

Q: Is CVE-2026-40688 actively exploited?

Active exploitation of CVE-2026-40688 has not been confirmed. Its EPSS score was 6.4% on 2026-10-25, the estimated probability of exploitation in the next 30 days.

Q: What is the CVSS score for CVE-2026-40688?

CVE-2026-40688 has a CVSS v3 base score of 7.2 (HIGH severity), with vector string CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H.

No exploitation reported by the sources we read.

Published2026-04-14
Fixed in8.0.4 · 7.6.7 · 7.4.12
WeaknessCWE-787

Am I affected?

With a domain, we read the version its public headers and pages expose. A distribution build can carry the fix under an older number.

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.

Timeline

dates in UTC

2026-04-1423:16CVE publishedNVD

Observed activity

isMalicious corpus · updated 2026-10-25 15:37 UTC

Indicators tagged with this CVE, per day0 indicators over 7 days

Block these indicators

Firewall list (EDL, text): https://api.ismalicious.com/edl/cve/CVE-2026-40688?format=txt
CSV export: https://api.ismalicious.com/edl/cve/CVE-2026-40688?format=csv
TAXII collection of exploited CVEs
The EDL and CSV take an API key on the Pro plan.

Versions per branch

NVD

Fortinet fortiweb

Branch	Affected	Fixed in	Source
8.0	≥ 8.0.0, < 8.0.4	8.0.4	NVD
7.6	≥ 7.6.0, < 7.6.7	7.6.7	NVD
7.4	≥ 7.4.0, < 7.4.12	7.4.12	NVD

as publishedRanges as NVD and OSV publish them; a distribution’s build can be fixed under an older number.

Fix

Update Fortinet fortiweb to 8.0.4 · 7.6.7 · 7.4.12

Advisories and patches

fortiguard.fortinet.comVendor Advisory

Detection

Nuclei template: none so far
Exploit-DB: no entry
Proof-of-concept repositories: none listed

Sources

NVDCVE recordread 2026-10-23
CISA-ADPSSVC decisionnone2026-04-15
OpenCVESSVC decisionnone—
CNACVSS 3.17.2read 2026-10-23
CNAweakness (CWE)CWE-787read 2026-10-23
FIRST EPSSEPSS score6.4 %2026-10-25

Technical details

CVSS v3 Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
Published: 2026-04-14
Last Modified: 2026-07-24
NVD status: Analyzed

Frequently asked questions

What is CVE-2026-40688?

Is CVE-2026-40688 actively exploited?

Active exploitation of CVE-2026-40688 has not been confirmed. Its EPSS score was 6.4% on 2026-10-25, the estimated probability of exploitation in the next 30 days.

What is the CVSS score for CVE-2026-40688?

CVE-2026-40688 has a CVSS v3 base score of 7.2 (HIGH severity), with vector string CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H.

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