Multiple Stored XSS
CVSSv3 Score: 4.3 An Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability [CWE-79] in FortiSandbox and FortiSandbox Cloud may allow a privileged attacker to perform a stored XSS attack via crafted HTTP requests. Revised on 2026-04-14 00:00:00
CSIRTS triage
- What
- A stored XSS vulnerability allows a privileged attacker to perform attacks via crafted HTTP requests.
- Who is affected
- Privileged users of FortiSandbox and FortiSandbox Cloud.
- Urgency
- Remediation is necessary due to the potential for exploitation, although it is not currently being exploited.
- Action
- Update 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-26-110
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-2026-398120.19% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 9% of all scored CVEs.
Referenced CVEs
| CVE | CSIRTS overview | External |
|---|---|---|
| CVE-2026-39812 | coverage & exploitation status | NVD · CVE.org |
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