CVE-2026-42836: Windows Function Discovery Service (fdwsd.dll) Elevation of Privilege Vulnerability
Concurrent execution using shared resource with improper synchronization ('race condition') in Function Discovery Service (fdwsd.dll) allows an authorized attacker to elevate privileges locally.
CSIRTS triage
- What
- Concurrent execution using shared resource with improper synchronization in Function Discovery Service allows an authorized attacker to elevate privileges locally.
- Who is affected
- Authorized users of the Function Discovery Service.
- Urgency
- Remediation is important due to the high severity of the vulnerability.
- Action
- Apply the security patch from Microsoft.
AI-assisted analysis generated from the source advisory — verify against the original.
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Details
Original advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-42836
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-2026-428360.20% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 10% of all scored CVEs.
Referenced CVEs
| CVE | CSIRTS overview | External |
|---|---|---|
| CVE-2026-42836 | coverage & exploitation status | NVD · CVE.org |
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