Out-Of-Bounds Write in administrative interface
CVSSv3 Score: 6.7 An out-of-bounds write vulnerability [CWE-787] in FortiWeb CGI daemon may allow a remote privileged attacker to execute arbitrary code or command via crafted HTTP requests. Revised on 2026-04-15 00:00:00
CSIRTS triage
- What
- An out-of-bounds write vulnerability may allow a remote privileged attacker to execute arbitrary code.
- Who is affected
- Privileged users of the FortiWeb administrative interface.
- Urgency
- Remediation is necessary due to the potential for arbitrary code execution.
- Action
- Update to the latest software version.
AI-assisted analysis generated from the source advisory — verify against the original.
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Details
Original advisory: https://fortiguard.fortinet.com/psirt/FG-IR-26-127
Exploitation outlook
EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.
- Moderate exploitation riskCVE-2026-406886.4% 30-day exploitation probability. Patch within normal cadence, watch for KEV listing. Riskier than 93% of all EPSS-scored CVEs.
Referenced CVEs
| CVE | CSIRTS overview | External |
|---|---|---|
| CVE-2026-40688 | coverage & exploitation status | NVD · CVE.org |
Recent advisories for Out-Of-Bounds Write in
A cluster of recent advisories against the same product widens the attack surface — attackers routinely chain freshly published CVEs on one product, so review these together.
- highCVE-2026-75770: Substance3D - Painter is affected by an out-of-bounds write vulnerability that could result in…nvd · 2026-08-25
- highCVE-2026-75749: Substance3D - Painter is affected by an out-of-bounds write vulnerability that could result in…nvd · 2026-08-25
- highCVE-2026-71564: Substance3D - Designer is affected by an out-of-bounds write vulnerability that could result i…nvd · 2026-08-25
- highCVE-2026-71382: Substance3D - Sampler is affected by an out-of-bounds write vulnerability that could result in…nvd · 2026-08-25
- highCVE-2026-48427: Substance3D - Designer is affected by an out-of-bounds write vulnerability that could result i…nvd · 2026-08-25
- highCVE-2026-48426: Substance3D - Designer is affected by an out-of-bounds write vulnerability that could result i…nvd · 2026-08-25
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