Bug#1142838: libsoup3: CVE-2026-12548

[Salvatore Bonaccorso]

Source: libsoup3
Version: 3.6.6-1
Severity: important
Tags: security upstream
Forwarded: https://gitlab.gnome.org/GNOME/libsoup/-/work_items/512
X-Debbugs-Cc: carnil at debian.org, Debian Security Team <team at security.debian.org>

Hi,

The following vulnerability was published for libsoup3.

CVE-2026-12548[0]:
| A heap out-of-bounds read flaw was found in libsoup. When parsing
| multipart HTTP messages, an integer type mismatch between the caller
| and soup_headers_parse() can cause the length parameter to be
| incorrectly truncated, leading to a heap buffer over-read. A remote
| attacker could use this flaw to crash an application using libsoup
| or potentially disclose heap memory contents.


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-2026-12548
    https://www.cve.org/CVERecord?id=CVE-2026-12548
[1] https://gitlab.gnome.org/GNOME/libsoup/-/work_items/512
[2] https://gitlab.gnome.org/GNOME/libsoup/-/merge_requests/524
[3] https://gitlab.gnome.org/GNOME/libsoup/-/commit/7334c38f1f6aa5e64207cb415cf2509838c52b37

Please adjust the affected versions in the BTS as needed.

Regards,
Salvatore