CVE-2026-66339
Last modified
CVE-2026-66339 is a medium-severity vulnerability rated 6.5/10 on the CVSS scale. A flaw was found in libsoup. After a CONNECT tunnel is established through an HTTP proxy, libsoup incorrectly attaches the Proxy-Authorization header to subsequent HTTPS requests sent through that tunnel to the destination server. EPSS estimates a 0.23% chance of exploitation in the next 30 days.
Description
A flaw was found in libsoup. After a CONNECT tunnel is established through an HTTP proxy, libsoup incorrectly attaches the Proxy-Authorization header to subsequent HTTPS requests sent through that tunnel to the destination server. This allows the destination server to capture proxy credentials, leading to information disclosure.
Metrics
Weakness Enumeration
Affected Software
| Vendor | Product | Versions |
|---|---|---|
| Gnome | Libsoup | All versions |
| Redhat | Enterprise Linux | 6.0 |
| Redhat | Enterprise Linux | 7.0 |
| Redhat | Enterprise Linux | 8.0 |
| Redhat | Enterprise Linux | 9.0 |
| Redhat | Enterprise Linux | 10.0 |
References
- https://access.redhat.com/security/cve/CVE-2026-66339Vendor Advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=2506951Issue Tracking, Vendor Advisory, Exploit, Mitigation
Timeline
- Published
- Last Modified
- Status
- Analyzed
Frequently Asked Questions
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How Strix Helps
- How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
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- PR ReviewsPentest every pull request so vulnerable code is caught before it ships to production.
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