CVE-2026-86413
Published Oct 20, 2026
Modified Oct 22, 2026
Description
When using an *ambient user* in a first transfer doing Negotiate authentication and asked to follow redirects, curl could pass on its credential details to an unrelated second origin when asked to redirect there.
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EPSS — Exploit Prediction
0.0073
Probability of exploitation
0.55%
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-2026-86413? +
When using an *ambient user* in a first transfer doing Negotiate
authentication and asked to follow redirects, curl could pass on its
credential details to an unrelated second origin when asked to redirect there.
How do I check if I'm vulnerable to CVE-2026-86413? +
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.
