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
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N
Weakness Enumeration
Affected Software
Source: CNA advisory (CVE.org). NVD analysis pending.
| Vendor | Product | Versions |
|---|---|---|
| Red Hat | Red Hat Enterprise Linux 10 | All versions |
| Red Hat | Red Hat Enterprise Linux 6 | All versions |
| Red Hat | Red Hat Enterprise Linux 7 | All versions |
| Red Hat | Red Hat Enterprise Linux 8 | All versions |
| Red Hat | Red Hat Enterprise Linux 9 | All versions |
References
Timeline
- Published
- Last Modified
- Status
- Awaiting Analysis
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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