Out-of-bounds access in CAPWAP daemon
CVSSv3 Score: 8.3 An Out-Of-Bounds Write vulnerability [CWE-787] in FortiOS capwap daemon may allow an attacker controlling an authenticated FortiAP FortiExtender or FortiSwitch to gain execution privileges on the FortiGate device Revised on 2026-05-12 00:00:00
CSIRTS triage
- What
- An out-of-bounds write vulnerability may allow attackers to gain execution privileges.
- Who is affected
- Authenticated users controlling FortiAP, FortiExtender, or FortiSwitch.
- Urgency
- Remediation is urgent due to the high severity and potential for privilege escalation.
- Action
- Apply patches as soon as they are available.
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-26-123
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-2025-538440.56% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 44% of all EPSS-scored CVEs.
Referenced CVEs
| CVE | CSIRTS overview | External |
|---|---|---|
| CVE-2025-53844 | coverage & exploitation status | NVD · CVE.org |
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