CVE-2026-3632CWE-1286

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

Low · published March 17, 2026

CVSS v3.1
3.9
EPSS
0%
Percentile
28.9
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v3.1
3.9 · LOW
Vector
CVSS:3.1/AV:N/AC:H/PR:H/UI:R/S:U/C:L/I:L/A:L
CVSS v4.0
Not supplied
EPSS
0.00363 · 28.9th percentile
Weakness
CWE-1286 · Improper Validation of Syntactic Correctness of Input
Published
2026-03-17T09:44Z
EPSS history
Timeline
  • 17 MAR 09:44Z
    Libsoup: libsoup: http smuggling and server-side request forgery via malformed hostnames
    cvelistv5