Open5GS up to 2.7.6 CCA denial of service

CVSS Meta Temp Score
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CTI Interest Score
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5.9$0-$5k0.71

Summaryinfo

A vulnerability was found in Open5GS up to 2.7.6. It has been declared as problematic. The impacted element is the function smf_gx_cca_cb/smf_gy_cca_cb/smf_s6b_aaa_cb/smf_s6b_sta_cb of the component CCA Handler. Such manipulation leads to denial of service. This vulnerability is uniquely identified as CVE-2026-4240. The attack can be launched remotely. Moreover, an exploit is present. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as problematic, has been found in Open5GS up to 2.7.6. Affected by this issue is the function smf_gx_cca_cb/smf_gy_cca_cb/smf_s6b_aaa_cb/smf_s6b_sta_cb of the component CCA Handler. The manipulation with an unknown input leads to a denial of service vulnerability. Using CWE to declare the problem leads to CWE-404. The product does not release or incorrectly releases a resource before it is made available for re-use. Impacted is availability.

The advisory is available at github.com. This vulnerability is handled as CVE-2026-4240. The exploitation is known to be easy. The attack may be launched remotely. No form of authentication is required for exploitation. Technical details as well as a public exploit are known. This vulnerability is assigned to T1499 by the MITRE ATT&CK project.

The exploit is available at github.com. It is declared as proof-of-concept.

Upgrading to version 2.7.7 eliminates this vulnerability. The upgrade is hosted for download at github.com. Applying the patch 80eb484a6ab32968e755e628b70d1a9c64f012ec is able to eliminate this problem. The bugfix is ready for download at github.com. The best possible mitigation is suggested to be upgrading to the latest version.

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Productinfo

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 6.0
VulDB Meta Temp Score: 5.9

VulDB Base Score: 5.3
VulDB Temp Score: 4.8
VulDB Vector: 🔒
VulDB Reliability: 🔍

NVD Base Score: 7.5
NVD Vector: 🔒

CNA Base Score: 5.3
CNA Vector: 🔒

CVSSv2info

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

Exploitinginfo

Class: Denial of service
CWE: CWE-404
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Access: Public
Status: Proof-of-Concept
Download: 🔒

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Open5GS 2.7.7
Patch: 80eb484a6ab32968e755e628b70d1a9c64f012ec

Timelineinfo

03/15/2026 Advisory disclosed
03/15/2026 +0 days VulDB entry created
03/21/2026 +6 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: 4343
Status: Confirmed

CVE: CVE-2026-4240 (🔒)
GCVE (CVE): GCVE-0-2026-4240
GCVE (VulDB): GCVE-100-351182
scip Labs: https://www.scip.ch/en/?labs.20161013

Entryinfo

Created: 03/15/2026 21:45
Updated: 03/21/2026 11:03
Changes: 03/15/2026 21:45 (60), 03/21/2026 11:03 (42)
Complete: 🔍
Submitter: ZiyuLin
Cache ID: 216::103

Submitinfo

Accepted

  • Submit #771361: Open5GS MME v2.7.6 Improper Authentication (by ZiyuLin)

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