Bug#1142846: libsoup3: CVE-2026-66339

[Salvatore Bonaccorso]

Source: libsoup3
Version: 3.6.6-1
Severity: important
Tags: security upstream
Forwarded: https://gitlab.gnome.org/GNOME/libsoup/-/work_items/534
X-Debbugs-Cc: carnil at debian.org, Debian Security Team <team at security.debian.org>

Hi,

The following vulnerability was published for libsoup3.

CVE-2026-66339[0]:
| 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.


If you fix the vulnerability please also make sure to include the
CVE (Common Vulnerabilities & Exposures) id in your changelog entry.

For further information see:

[0] https://security-tracker.debian.org/tracker/CVE-2026-66339
    https://www.cve.org/CVERecord?id=CVE-2026-66339
[1] https://gitlab.gnome.org/GNOME/libsoup/-/work_items/534

Please adjust the affected versions in the BTS as needed.

Regards,
Salvatore