CVE-2026-6324
Libsoup: libsoup: http request smuggling via unsigned to signed conversion error
A flaw was found in libsoup. A remote attacker could exploit an unsigned to signed conversion error in the `soup_body_input_stream_read_chunked()` function by sending a malicious HTTP request. This vulnerability occurs when libsoup operates behind a non-libsoup proxy server or as a proxy in front of a non-libsoup backend server. Successful exploitation can allow an attacker to bypass security controls, poison web caches, or gain unauthorized access.
Fixes and workarounds
No remediation reported in collected sources.
Missing remediation information is not evidence that no patch exists.
Affected products and versions
| Product | Versions | Authority |
|---|---|---|
| Red Hat Enterprise Linux 10 Red Hat libsoup3
https://access.redhat.com/downloads/content/package-browser/ |
Range not reported
Other versions: affected |
CNA: redhat |
| Red Hat Enterprise Linux 6 Red Hat libsoup
https://access.redhat.com/downloads/content/package-browser/ |
Range not reported
Other versions: affected |
CNA: redhat |
| Red Hat Enterprise Linux 7 Red Hat libsoup
https://access.redhat.com/downloads/content/package-browser/ |
Range not reported
Other versions: affected |
CNA: redhat |
| Red Hat Enterprise Linux 8 Red Hat libsoup
https://access.redhat.com/downloads/content/package-browser/ |
Range not reported
Other versions: affected |
CNA: redhat |
| Red Hat Enterprise Linux 9 Red Hat libsoup
https://access.redhat.com/downloads/content/package-browser/ |
Range not reported
Other versions: affected |
CNA: redhat |
Version ranges are source assertions. Check the vendor advisory and your installed configuration before determining exposure.
CVSS assessments
| Version / score | Vector | Authority |
|---|---|---|
| 3.1 / 4.8 medium |
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N | CNA: redhat |
Exploit evidence
- https://gitlab.gnome.org/GNOME/libsoup/-/work_items/508
exploit · ADP: CISA-ADP
References
- https://access.redhat.com/security/cve/CVE-2026-6324CNA: redhat · vdb-entry, x_refsource_REDHAT
- https://bugzilla.redhat.com/show_bug.cgi?id=2458479CNA: redhat · issue-tracking, x_refsource_REDHAT
- https://gitlab.gnome.org/GNOME/libsoup/-/commit/96ac392b444d01bd5de1d1276b187c3ed49d048cCNA: redhat
- https://gitlab.gnome.org/GNOME/libsoup/-/issues/508CNA: redhat
- https://gitlab.gnome.org/GNOME/libsoup/-/work_items/508ADP: CISA-ADP · exploit
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