Vulnerability Report

CVE-2026-3632

Title: libsoup hostname validation bypass leads to HTTP smuggling

SSRF

Proof Of Concept

No public PoC currently indexed for CVE-2026-3632.

CWE Category CWE-1286

Published Date Mar 17, 2026

Modified Date Mar 19, 2026

Exploit Status Not Found

Score 3.9 CVSS v3.1

Exploit Probability (EPSS)

0.13%

Vulnerability Summary

CVE-2026-3632: 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.

Impacted Vendors

libsoup 1

gnome 1

Reference Links

https://access.redhat.com/security/cve/CVE-2026-3632 https://bugzilla.redhat.com/show_bug.cgi?id=2445127 https://gitlab.gnome.org/GNOME/libsoup/-/issues/483

CVSS v3.1

Source Entity [email protected]

Severity LOW

3.9

Attack Vector

NETWORK

Complexity

HIGH

Privileges

N/A

Interaction

REQUIRED

Confidentiality

N/A

Integrity

N/A

Availability

N/A

Scope

UNCHANGED

RAW VECTOR CVSS:3.1/AV:N/AC:H/PR:H/UI:R/S:U/C:L/I:L/A:L

CVSS v3.1

Source Entity [email protected]

Severity MEDIUM

5.5

Attack Vector

NETWORK

Complexity

LOW

Privileges

N/A

Interaction

REQUIRED

Confidentiality

N/A

Integrity

N/A

Availability

N/A

Scope

UNCHANGED

RAW VECTOR CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:L

Associated Attack Patterns (CAPEC)

Total: Patterns

CVE-2026-3632 Exploits & PoCs (Proof Of Concept)

No public PoCs found in our database for this CVE.

March 19, 2026 MODIFIED

Vulnerability data updated via NVD.

March 19, 2026 MODIFIED

Vulnerability data updated via NVD.

March 17, 2026 MODIFIED

Vulnerability data updated via NVD.

March 17, 2026 MODIFIED

Vulnerability data updated via NVD.

Attack Vector Matrix

Access Vector NETWORK

Complexity HIGH

Privileges N/A

Interaction REQUIRED

CVSS Vector String


                                    CVSS:3.1/AV:N/AC:H/PR:H/UI:R/S:U/C:L/I:L/A:L

Affected Stack

No specific products linked.