Open5GS up to 2.7.6 AMF/MME src/amf/context.c ran_ue_find_by_amf_ue_ngap_id improper authorization

CVSS Meta Temp Score
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CTI Interest Score
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6.0$0-$5k0.00

Summaryinfo

A vulnerability categorized as critical has been discovered in Open5GS up to 2.7.6. Affected is the function ran_ue_find_by_amf_ue_ngap_id of the file src/amf/context.c of the component AMF/MME. Executing a manipulation can lead to improper authorization. This vulnerability is registered as CVE-2026-8743. It is possible to launch the attack remotely. Furthermore, an exploit is available. A patch should be applied to remediate this issue.

Detailsinfo

A vulnerability classified as critical was found in Open5GS up to 2.7.6. This vulnerability affects the function ran_ue_find_by_amf_ue_ngap_id of the file src/amf/context.c of the component AMF/MME. The manipulation with an unknown input leads to a improper authorization vulnerability. The CWE definition for the vulnerability is CWE-285. The product does not perform or incorrectly performs an authorization check when an actor attempts to access a resource or perform an action. As an impact it is known to affect confidentiality, integrity, and availability.

The weakness was published by Seungjoon Na and Jinha Kim with Kookmin University ICSR Lab as 4498. The advisory is available at github.com. This vulnerability was named CVE-2026-8743. The exploitation appears to be easy. The attack can be initiated remotely. Technical details and also a public exploit are known. This vulnerability is assigned to T1548.002 by the MITRE ATT&CK project.

It is possible to download the exploit at github.com. It is declared as proof-of-concept.

Applying the patch 5746b8576cfceec18ed87eb7d8cf11b1fb4cd8b1 is able to eliminate this problem. The bugfix is ready for download at github.com.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2026-30691). If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

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Version

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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: 6.3
VulDB Meta Temp Score: 6.0

VulDB Base Score: 6.3
VulDB Temp Score: 5.7
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 6.3
CNA Vector: 🔒

CVSSv2info

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

Exploitinginfo

Class: Improper authorization
CWE: CWE-285 / CWE-266
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: Patch
Status: 🔍

0-Day Time: 🔒

Patch: 5746b8576cfceec18ed87eb7d8cf11b1fb4cd8b1

Timelineinfo

05/16/2026 Advisory disclosed
05/16/2026 +0 days VulDB entry created
05/21/2026 +5 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: 4498
Researcher: Seungjoon Na, Jinha Kim
Organization: Kookmin University ICSR Lab
Status: Confirmed
Confirmation: 🔒

CVE: CVE-2026-8743 (🔒)
GCVE (CVE): GCVE-0-2026-8743
GCVE (VulDB): GCVE-100-364330
EUVD: 🔒
scip Labs: https://www.scip.ch/en/?labs.20161013

Entryinfo

Created: 05/16/2026 14:43
Updated: 05/21/2026 14:33
Changes: 05/16/2026 14:43 (60), 05/17/2026 10:21 (4), 05/17/2026 13:07 (1), 05/17/2026 16:11 (3), 05/21/2026 09:13 (1), 05/21/2026 14:33 (31)
Complete: 🔍
Submitter: Seungjoon Na
Committer: Seungjoon Na
Cache ID: 216::103

Submitinfo

Accepted

  • Submit #814559: Open5GS 2.7.6 Incorrect Authorization (by Seungjoon Na)

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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