VDB
CVE-2026-86414
CVE-2026-86414
PUBLISHED
CVSS 9.1 CRITICAL
Reported by curl · Published October 20, 2026
An HTTP proxy can trick libcurl into sending the origin's credentials (Basic password, or a Negotiate/Kerberos ticket) to the proxy itself, by answering the `CONNECT` tunnel request with 401 `WWW-Authenticate:` instead of the expected 407 `Proxy-Authenticate:`.
Risk Scores
CVSS 3.1
9.1
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| curl | curl | 8.22.0, 8.21.0, 8.20.0 |
| curl | curl | 7.10.8, 8.22.0, 8.21.0 |
| alpine | curl | 0 |
Timeline
- CVE Published
- Oct 14, 2026 PoC Published
- Oct 21, 2026 EPSS Score
- Oct 24, 2026 EPSS Score
- Oct 25, 2026 EPSS Score
- Oct 27, 2026 EPSS Score
- Oct 29, 2026 EPSS Score
- Oct 31, 2026 EPSS Score