How severe is CVE-2026-24640?

CVE-2026-24640 has a CVSS 3.x base score of 6.6, rated medium severity. It is exploitable over network with high attack complexity, requires high privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2026-24640 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (46th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-24640?

CVE-2026-24640 affects Fortinet Fortiweb. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-24640?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2026-24640 have an EU (EUVD) identifier?

Yes. CVE-2026-24640 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-10522.

When was CVE-2026-24640 published?

CVE-2026-24640 was published on 2026-03-10 and last updated on 2026-06-17.

CVE-2026-24640

CVE-2026-24640 is a medium-severity vulnerability in Fortinet Fortiweb with a CVSS 3.x base score of 6.6. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-787.

Key facts

Severity: Medium (CVSS 3.x base score 6.6)
EPSS exploit prediction: 1% (46th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-10522
Weakness: CWE-787
Affected product: Fortinet Fortiweb
Published: 2026-03-10
Last modified: 2026-06-17

Description

A Stack-based Buffer Overflow vulnerability [CWE-121] vulnerability in Fortinet FortiWeb 8.0.0 through 8.0.2, FortiWeb 7.6.0 through 7.6.6, FortiWeb 7.4 all versions, FortiWeb 7.2 all versions, FortiWeb 7.0.2 through 7.0.12 may allow a remote authenticated attacker who can bypass stack protection and ASLR to execute arbitrary code or commands via crafted HTTP requests.

Frequently asked questions

What is CVE-2026-24640?: A Stack-based Buffer Overflow vulnerability [CWE-121] vulnerability in Fortinet FortiWeb 8.0.0 through 8.0.2, FortiWeb 7.6.0 through 7.6.6, FortiWeb 7.4 all versions, FortiWeb 7.2 all versions, FortiWeb 7.0.2 through 7.0.12 may allow a remote authenticated attacker who can bypass stack protection and ASLR to execute arbitrary code or commands via crafted HTTP requests.
How severe is CVE-2026-24640?: CVE-2026-24640 has a CVSS 3.x base score of 6.6, rated medium severity. It is exploitable over network with high attack complexity, requires high privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2026-24640 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (46th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-24640?: CVE-2026-24640 affects Fortinet Fortiweb. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-24640?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-24640 have an EU (EUVD) identifier?: Yes. CVE-2026-24640 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-10522.
When was CVE-2026-24640 published?: CVE-2026-24640 was published on 2026-03-10 and last updated on 2026-06-17.

References

https://fortiguard.fortinet.com/psirt/FG-IR-26-087

Affected products (1)

cpe:2.3:a:fortinet:fortiweb:*:*:*:*:*:*:*:*

More vulnerabilities in Fortinet Fortiweb

CVE-2026-24858 — Critical (CVSS 9.8): An Authentication Bypass Using an Alternate Path or Channel vulnerability [CWE-288] vulnerability in Fortinet…
CVE-2025-59719 — Critical (CVSS 9.8): An improper verification of cryptographic signature vulnerability in Fortinet FortiWeb 8.0.0, FortiWeb 7.6.0 through…
CVE-2025-64446 — Critical (CVSS 9.8): A relative path traversal vulnerability in Fortinet FortiWeb 8.0.0 through 8.0.1, FortiWeb 7.6.0 through 7.6.4,…
CVE-2025-25257 — Critical (CVSS 9.8): An improper neutralization of special elements used in an SQL command ('SQL Injection') vulnerability [CWE-89]…
CVE-2023-25610 — Critical (CVSS 9.8): A buffer underwrite ('buffer underflow') vulnerability in the administrative interface of Fortinet FortiOS version…
CVE-2021-42756 — Critical (CVSS 9.8): Multiple stack-based buffer overflow vulnerabilities [CWE-121] in the proxy daemon of FortiWeb 5.x all versions,…

All CVEs affecting Fortinet Fortiweb →

Other CWE-787 (Out-of-bounds Write) vulnerabilities

CVE-2026-42369 — Critical (CVSS 10.0): GV-VMS V20 is a Video Monitoring Software used to gather the feeds of many surveillance cameras and manage other…
CVE-2026-4746 — Critical (CVSS 10.0): Out-of-bounds Write vulnerability in timeplus-io proton (base/poco/Foundation/src‎ modules). This vulnerability is…
CVE-2025-43300 — Critical (CVSS 10.0): An out-of-bounds write issue was addressed with improved bounds checking. This issue is fixed in iOS 15.8.5 and iPadOS…
CVE-2025-24201 — Critical (CVSS 10.0): An out-of-bounds write issue was addressed with improved checks to prevent unauthorized actions. This issue is fixed in…
CVE-2024-42479 — Critical (CVSS 10.0): llama.cpp provides LLM inference in C/C++. The unsafe `data` pointer member in the `rpc_tensor` structure can cause…
CVE-2024-39791 — Critical (CVSS 10.0): Stack-based buffer overflow vulnerabilities affecting Vonets industrial wifi bridge relays and wifi bridge…

Browse all CWE-787 (Out-of-bounds Write) vulnerabilities →