CVE-2026-66339
Publication date 24 July 2026
Last updated 21 October 2026
Ubuntu priority
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.
Status
| Package | Ubuntu Release | Status |
|---|---|---|
| libsoup2.4 | 26.10 stonking |
Vulnerable
|
| 26.04 LTS resolute |
Fixed in 2.74.3-10.1ubuntu5+esm3
|
|
| 24.04 LTS noble |
Fixed in 2.74.3-6ubuntu1.9
|
|
| 22.04 LTS jammy |
Fixed in 2.74.2-3ubuntu0.9
|
|
| 20.04 LTS focal |
Fixed in 2.70.0-1ubuntu0.5+esm4
|
|
| 18.04 LTS bionic |
Fixed in 2.62.1-1ubuntu0.4+esm9
|
|
| 16.04 LTS xenial |
Fixed in 2.52.2-1ubuntu0.3+esm8
|
|
| libsoup3 | 26.10 stonking |
Fixed in 3.6.6-1ubuntu3
|
| 26.04 LTS resolute |
Fixed in 3.6.6-1ubuntu0.1
|
|
| 24.04 LTS noble |
Fixed in 3.4.4-5ubuntu0.9
|
|
| 22.04 LTS jammy |
Fixed in 3.0.7-0ubuntu1+esm9
|
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CVSS version: CVSS v3.0
Base score
6.5 · Medium
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N
References
Related Ubuntu Security Notices (USN)
- USN-8890-1
- libsoup vulnerabilities
- 6 October 2026
- USN-8890-2
- libsoup vulnerabilities
- 21 October 2026