CVE-2026-3632

LOW

Libsoup: libsoup: http smuggling and server-side request forgery via malformed hostnames

Title source: cna
STIX 2.1

Description

A flaw was found in libsoup, a library used by applications to send network requests. This vulnerability occurs because libsoup does not properly validate hostnames, allowing special characters to be injected into HTTP headers. A remote attacker could exploit this to perform HTTP smuggling, where they can send hidden, malicious requests alongside legitimate ones. In certain situations, this could lead to Server-Side Request Forgery (SSRF), enabling an attacker to force the server to make unauthorized requests to other internal or external systems. The impact is low, as SoupServer is not actually used in internet infrastructure.

References (3)

Core 3
Core References
Vdb Entry, X_Refsource_Redhat vdb-entry x_refsource_redhat
https://access.redhat.com/security/cve/CVE-2026-3632
Issue Tracking, X_Refsource_Redhat issue-tracking x_refsource_redhat
RHBZ#2445127
https://bugzilla.redhat.com/show_bug.cgi?id=2445127

Scores

CVSS v3 3.9
EPSS 0.0021
EPSS Percentile 10.8%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:H/PR:H/UI:R/S:U/C:L/I:L/A:L

CISA SSVC

Vulnrichment
Exploitation none
Automatable no
Technical Impact partial

Details

CWE
CWE-1286
Status published
Products (11)
gnome/libsoup
Red Hat/Red Hat Enterprise Linux 10
Red Hat/Red Hat Enterprise Linux 6
Red Hat/Red Hat Enterprise Linux 7
Red Hat/Red Hat Enterprise Linux 8
Red Hat/Red Hat Enterprise Linux 9
redhat/enterprise_linux 6.0
redhat/enterprise_linux 7.0
redhat/enterprise_linux 8.0
redhat/enterprise_linux 9.0
... and 1 more
Published Mar 17, 2026
Tracked Since Mar 17, 2026