GNOME libsoup Content-Type Header response splitting

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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5.9$0-$5k0.00

Summaryinfo

A vulnerability identified as critical has been detected in GNOME libsoup. This impacts an unknown function of the component Content-Type Header Handler. This manipulation causes response splitting. This vulnerability is registered as CVE-2026-3634. Remote exploitation of the attack is possible. No exploit is available.

Detailsinfo

A vulnerability classified as critical was found in GNOME libsoup (affected version not known). Affected by this vulnerability is some unknown functionality of the component Content-Type Header Handler. The manipulation with an unknown input leads to a response splitting vulnerability. The CWE definition for the vulnerability is CWE-113. The product receives data from an HTTP agent/component (e.g., web server, proxy, browser, etc.), but it does not neutralize or incorrectly neutralizes CR and LF characters before the data is included in outgoing HTTP headers. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

A flaw was found in libsoup. An attacker controlling the value used to set the Content-Type header can inject a Carriage Return Line Feed (CRLF) sequence due to improper input sanitization in the `soup_message_headers_set_content_type()` function. This vulnerability allows for the injection of arbitrary header-value pairs, potentially leading to HTTP header injection and response splitting attacks.

It is possible to read the advisory at bugzilla.redhat.com. This vulnerability is known as CVE-2026-3634. The exploitation appears to be easy. The attack can be launched remotely. The exploitation doesn't need any form of authentication. The technical details are unknown and an exploit is not publicly available. The pricing for an exploit might be around USD $0-$5k at the moment (estimation calculated on 04/08/2026).

The vulnerability scanner Nessus provides a plugin with the ID 301504 (Linux Distros Unpatched Vulnerability : CVE-2026-3634), which helps to determine the existence of the flaw in a target environment.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

The vulnerability is also documented in the databases at Tenable (301504) and CERT Bund (WID-SEC-2026-1007). Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Affected

  • IBM App Connect Enterprise

Productinfo

Vendor

Name

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.9
VulDB Meta Temp Score: 5.9

VulDB Base Score: 7.3
VulDB Temp Score: 7.3
VulDB Vector: 🔒
VulDB Reliability: 🔍

NVD Base Score: 6.5
NVD Vector: 🔒

CNA Base Score: 3.9
CNA Vector: 🔒

CVSSv2info

AVACAuCIA
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Response splitting
CWE: CWE-113 / CWE-93 / CWE-74
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Nessus ID: 301504
Nessus Name: Linux Distros Unpatched Vulnerability : CVE-2026-3634

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Timelineinfo

03/06/2026 Advisory disclosed
03/06/2026 +0 days VulDB entry created
04/08/2026 +33 days VulDB entry last update

Sourcesinfo

Vendor: gnome.org

Advisory: bugzilla.redhat.com
Status: Not defined

CVE: CVE-2026-3634 (🔒)
GCVE (CVE): GCVE-0-2026-3634
GCVE (VulDB): GCVE-100-349435
CERT Bund: WID-SEC-2026-1007 - IBM App Connect Enterprise: Mehrere Schwachstellen

Entryinfo

Created: 03/06/2026 11:37
Updated: 04/08/2026 22:14
Changes: 03/06/2026 11:37 (48), 03/09/2026 22:32 (2), 03/21/2026 18:45 (22), 04/08/2026 22:14 (7)
Complete: 🔍
Cache ID: 216::103

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

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