CVE-2026-86414

CVE-2026-86414

published October 21, 2026

CVSS
—
EPSS
0%
Percentile
20.6
In the wild
Unconfirmed
What it is

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:`.

The record
Technical detail
CVSS
Not scored
CVSS v4.0
Not supplied
EPSS
0.00291 · 20.6th percentile
Published
2026-10-21T01:17Z
References (3)
https://curl.se/docs/CVE-2026-86414.html · 2499f714-1537-4658-8207-48ae4bb9eae9https://curl.se/docs/CVE-2026-86414.json · 2499f714-1537-4658-8207-48ae4bb9eae9https://hackerone.com/reports/3993566 · 2499f714-1537-4658-8207-48ae4bb9eae9
EPSS history
Timeline
  • 22 OCT 03:35Z
    EPSS moved — → 0%
    epss
  • 20 OCT 20:07Z
    leaking host credentials to HTTP proxy
    cvelistv5
  • 20 OCT 20:07Z
    leaking host credentials to HTTP proxy
    cvelistv5