Free5GC up to 4.2.1 UPI Endpoint missing authentication

CVSS Meta Temp Score
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CTI Interest Score
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8.5$0-$5k0.00

Summaryinfo

A vulnerability identified as critical has been detected in Free5GC up to 4.2.1. This affects an unknown part of the component UPI Endpoint. This manipulation causes missing authentication. This vulnerability is registered as CVE-2026-44329. Remote exploitation of the attack is possible. No exploit is available. You should upgrade the affected component.

Detailsinfo

A vulnerability classified as critical was found in Free5GC up to 4.2.1. Affected by this vulnerability is some unknown functionality of the component UPI Endpoint. The manipulation with an unknown input leads to a missing authentication vulnerability. The CWE definition for the vulnerability is CWE-306. The product does not perform any authentication for functionality that requires a provable user identity or consumes a significant amount of resources. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

free5GC is an open-source implementation of the 5G core network. Prior to 4.2.2, free5GC's SMF mounts the UPI management route group without OAuth2/bearer-token authorization middleware. A network attacker who can reach SMF on the SBI can hit UPI endpoints with no Authorization header at all, and the requests reach the SMF business handlers. In the running Docker lab this was directly demonstrated for read (GET /upi/v1/upNodesLinks), write (POST /upi/v1/upNodesLinks with attacker-controlled UP-node and link payload), and delete (DELETE /upi/v1/upNodesLinks/{nodeID}) operations. This vulnerability is fixed in 4.2.2.

The advisory is shared at github.com. This vulnerability is known as CVE-2026-44329 since 05/05/2026. The exploitation appears to be easy. The attack can be launched remotely. The exploitation doesn't need any form of authentication. Neither technical details nor an exploit are publicly available.

Upgrading to version 4.2.2 eliminates this vulnerability.

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Productinfo

Name

Version

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 8.6
VulDB Meta Temp Score: 8.5

VulDB Base Score: 7.3
VulDB Temp Score: 7.0
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 10.0
CNA Vector (GitHub_M): 🔒

CVSSv2info

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

Exploitinginfo

Class: Missing authentication
CWE: CWE-306 / CWE-287
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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Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Free5GC 4.2.2

Timelineinfo

05/05/2026 CVE reserved
05/27/2026 +22 days Advisory disclosed
05/27/2026 +0 days VulDB entry created
05/27/2026 +0 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: github.com
Status: Confirmed

CVE: CVE-2026-44329 (🔒)
GCVE (CVE): GCVE-0-2026-44329
GCVE (VulDB): GCVE-100-366445

Entryinfo

Created: 05/27/2026 19:08
Changes: 05/27/2026 19:08 (63)
Complete: 🔍
Cache ID: 216::103

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