CVE-2026-86413
When using an *ambient user* in a first transfer doing Negotiate authentication and asked to follow…
- Risk score
- 65/100
- CVSS
- 9.1 v3.1
- Exploit chance (30 days)
- 0.3%
- Published
- 20 Oct 2026
Open in the live forecast Today's forecast
What to know
- What it is
- 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.
- Affected
- See advisory
- Fix
- Apply the vendor's security update; see the linked advisory.
- Exploitation
- No known exploitation
Why it is Amber
- CVSS 9.1 critical
- Remotely exploitable without logging in
References
Original 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.
Last activity 20 Oct 2026. Patch Forecast updates every hour.