Description
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.
Published: 2026-10-15
Score: 8.2 High
EPSS: < 1% Very Low
KEV: No
Impact: n/a
Action: n/a
AI Analysis

No analysis available yet.

Remediation

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Tracking

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Advisories

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History

Thu, 15 Oct 2026 14:30:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'poc', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Thu, 15 Oct 2026 13:30:00 +0000

Type Values Removed Values Added
Description 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.
Weaknesses CWE-200
References
Metrics cvssV4_0

{'score': 8.2, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N'}

Subscriptions

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cve-icon MITRE

Status: PUBLISHED

Assigner: eclipse

Published:

Updated: 2026-10-15T13:50:52.566Z

Reserved: 2026-08-21T08:58:54.421Z

Link: CVE-2026-77711

cve-icon Vulnrichment

Updated: 2026-10-15T13:50:46.699Z

cve-icon NVD

Status : Awaiting Analysis

Published: 2026-10-15T09:17:18.573

Modified: 2026-10-15T14:41:34.110

Link: CVE-2026-77711

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

No data.

Weaknesses
  • CWE-200

    Exposure of Sensitive Information to an Unauthorized Actor