MajorCritical vulnerability

CVE-2026-77711 (CVSS 8.2)

NVD · officialPublished Oct 15, 2026Risk 37/100EPSS 0.3%

When Jetty's `HttpClient` make a request to a server through a forward proxy, the server may reply with a 407 (Proxy Authentication Required). The client mistakenly interprets the 407 as coming from the proxy, so it re-sends the request with the `Proxy-Authentication` header, which arrives to the server, that now has access to the proxy credentials.

Technical details

CVSS

8.2

AV:NetworkAC:LowPR:NoneUI:None

Evidence and sources

This record is attributed to NVD. Exploitation status and remediation guidance are kept separate from the vulnerability's technical severity.

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