Free5GC up to 4.2.1 PfdChangeNotifier.FlushNotifications denial of service

CVSS Meta Temp Score
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CTI Interest Score
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6.3$0-$5k0.00

Summaryinfo

A vulnerability was found in Free5GC up to 4.2.1. It has been classified as problematic. Affected by this vulnerability is the function PfdChangeNotifier.FlushNotifications. Performing a manipulation results in denial of service. This vulnerability is cataloged as CVE-2026-44319. It is possible to initiate the attack remotely. There is no exploit available. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability classified as problematic has been found in Free5GC up to 4.2.1. This affects the function PfdChangeNotifier.FlushNotifications. The manipulation with an unknown input leads to a denial of service vulnerability. CWE is classifying the issue as CWE-404. The product does not release or incorrectly releases a resource before it is made available for re-use. This is going to have an impact on availability. The summary by CVE is:

free5GC is an open-source implementation of the 5G core network. Prior to 4.2.2, free5GC's NEF terminates the entire process when a stored PFD-subscription notifyUri cannot be reached. In PfdChangeNotifier.FlushNotifications(), the notifier calls NnefPFDmanagementNotify(...) and on any delivery error invokes logger.PFDManageLog.Fatal(err), which is os.Exit(1)-equivalent in Go. An attacker who can create a PFD subscription with an attacker-chosen notifyUri and then trigger a PFD change can deterministically kill NEF on the asynchronous delivery attempt -- the process exits with status 1, dropping NEF's entire SBI surface until restart. This vulnerability is fixed in 4.2.2.

It is possible to read the advisory at github.com. This vulnerability is uniquely identified as CVE-2026-44319 since 05/05/2026. The exploitability is told to be easy. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. Technical details of the vulnerability are known, but there is no available exploit. The attack technique deployed by this issue is T1499 according to MITRE ATT&CK.

Upgrading to version 4.2.2 eliminates this vulnerability.

Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

Name

Version

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.4
VulDB Meta Temp Score: 6.3

VulDB Base Score: 5.3
VulDB Temp Score: 5.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 7.5
CNA Vector (GitHub_M): 🔒

CVSSv2info

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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: 🔒
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-2026-44319 (🔒)
GCVE (CVE): GCVE-0-2026-44319
GCVE (VulDB): GCVE-100-366399

Entryinfo

Created: 05/27/2026 18:55
Changes: 05/27/2026 18:55 (63)
Complete: 🔍
Cache ID: 216::103

Be aware that VulDB is the high quality source for vulnerability data.

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