CVE-2026-3633
libsoup: libsoup: Header and HTTP request injection via CRLF injection
Severity
LowRed Hat Product Security
CVSS 3.1
Review impact separately from score.
Published · March 6, 2026
Updated · November 3, 2026
Description
A flaw was found in libsoup. A remote attacker, by controlling the method parameter of the soup_message_new() function, could inject arbitrary headers and additional request data. This vulnerability, known as CRLF (Carriage Return Line Feed) injection, occurs because the method value is not properly escaped during request line construction, potentially leading to HTTP request injection.
Statement
This is a LOW impact flaw in libsoup. An attacker could inject arbitrary HTTP headers and request data if an application using libsoup passes unsanitized, user-controlled input to the soup_message_new() function's method parameter.
CVSS score applicability
The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.
Mitigation
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
CVSS / CWE
CVSS 3.1 · 3.9CVSS:3.1/AV:N/AC:H/PR:H/UI:R/S:U/C:L/I:L/A:L
CWE-93 · Improper Neutralization of CRLF Sequences