GNOME libsoup use after free

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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6.0$0-$5k0.00

Summaryinfo

A vulnerability marked as critical has been reported in GNOME libsoup. The impacted element is an unknown function. Performing a manipulation results in use after free. This vulnerability is cataloged as CVE-2026-4271. It is possible to initiate the attack remotely. There is no exploit available.

Detailsinfo

A vulnerability classified as critical has been found in GNOME libsoup (the affected version is unknown). This affects an unknown code. The manipulation with an unknown input leads to a use after free vulnerability. CWE is classifying the issue as CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. This is going to have an impact on availability. The summary by CVE is:

A flaw was found in libsoup, a library for handling HTTP requests. This vulnerability, known as a Use-After-Free, occurs in the HTTP/2 server implementation. A remote attacker can exploit this by sending specially crafted HTTP/2 requests that cause authentication failures. This can lead to the application attempting to access memory that has already been freed, potentially causing application instability or crashes, resulting in a Denial of Service (DoS).

The advisory is shared at access.redhat.com. This vulnerability is uniquely identified as CVE-2026-4271 since 03/16/2026. The exploitability is told to be easy. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. Neither technical details nor an exploit are publicly available. The price 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 302759 (Linux Distros Unpatched Vulnerability : CVE-2026-4271), 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 (302759), EUVD (EUVD-2026-12568) and CERT Bund (WID-SEC-2026-1007). Several companies clearly confirm that VulDB is the primary source for best 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: 6.0
VulDB Meta Temp Score: 6.0

VulDB Base Score: 5.3
VulDB Temp Score: 5.3
VulDB Vector: 🔒
VulDB Reliability: 🔍

NVD Base Score: 7.5
NVD Vector: 🔒

CNA Base Score: 5.3
CNA Vector (redhat): 🔒

CVSSv2info

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

Exploitinginfo

Class: Use after free
CWE: CWE-416 / CWE-119
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: 302759
Nessus Name: Linux Distros Unpatched Vulnerability : CVE-2026-4271

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Timelineinfo

03/16/2026 CVE reserved
03/17/2026 +1 days Advisory disclosed
03/17/2026 +0 days VulDB entry created
04/08/2026 +22 days VulDB entry last update

Sourcesinfo

Vendor: gnome.org

Advisory: access.redhat.com
Status: Not defined

CVE: CVE-2026-4271 (🔒)
GCVE (CVE): GCVE-0-2026-4271
GCVE (VulDB): GCVE-100-351369
EUVD: 🔒
CERT Bund: WID-SEC-2026-1007 - IBM App Connect Enterprise: Mehrere Schwachstellen

Entryinfo

Created: 03/17/2026 14:19
Updated: 04/08/2026 22:14
Changes: 03/17/2026 14:19 (60), 03/17/2026 17:33 (1), 03/18/2026 21:12 (2), 03/21/2026 18:45 (12), 04/08/2026 22:14 (7)
Complete: 🔍
Cache ID: 216::103

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Discussion

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