CVE-2026-87861
Published Oct 20, 2026
Modified Oct 22, 2026
Description
When using ambient user credentials, an HTTP request directed to one origin may be dispatched over a connection previously authenticated via Negotiate for a different origin, leaving the request's intended credentials unused.
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EPSS — Exploit Prediction
0.0068
Probability of exploitation
0.53%
Percentile rank
EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.
References
Frequently Asked Questions
What is CVE-2026-87861? +
When using ambient user credentials, an HTTP request directed to one origin
may be dispatched over a connection previously authenticated via Negotiate for
a different origin, leaving the request's intended credentials unused.
How do I check if I'm vulnerable to CVE-2026-87861? +
You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.
