Integer Overflow Denial of Service in administrative interface
CVSSv3 Score: 4.4 An Integer Overflow or Wraparound vulnerability [CWE-190] in FortiWeb may allow a privileged authenticated attacker to perform a denial of service of the system via crafted HTTP requests. Revised on 2026-04-14 00:00:00
CSIRTS triage
- What
- An integer overflow vulnerability allows a privileged authenticated attacker to cause a denial of service.
- Who is affected
- Privileged users of FortiWeb.
- Urgency
- Remediation is important to prevent service disruption.
- Action
- Update FortiWeb to the latest version to mitigate the vulnerability.
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-26-108
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.
- Low exploitation riskCVE-2026-398110.37% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 29% of all scored CVEs.
Referenced CVEs
| CVE | CSIRTS overview | External |
|---|---|---|
| CVE-2026-39811 | coverage & exploitation status | NVD · CVE.org |
Recent advisories for Integer Overflow Denial
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.
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