free5GC: NEF crashes via logger.Fatal on PFD notification delivery failure (attacker-controlled notifyUri)
Summary
| CVE | CVE-2026-44319 |
|---|---|
| State | PUBLISHED |
| Assigner | GitHub_M |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-05-27 17:16:37 UTC |
| Updated | 2026-05-28 17:50:05 UTC |
| Description | 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. |
Risk And Classification
Primary CVSS: v3.1 7.5 HIGH from [email protected]
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS: 0.000920000 probability, percentile 0.258200000 (date 2026-06-01)
Problem Types: CWE-20 | CWE-617 | CWE-755 | CWE-20 CWE-20: Improper Input Validation | CWE-617 CWE-617: Reachable Assertion | CWE-755 CWE-755: Improper Handling of Exceptional Conditions
| Version | Source | Type | Score | Severity | Vector |
|---|---|---|---|---|---|
| 3.1 | [email protected] | Secondary | 7.5 | HIGH | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
| 3.1 | CNA | DECLARED | 7.5 | HIGH | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
CVSS v3.1 Breakdown
Attack Vector
NetworkAttack Complexity
LowPrivileges Required
NoneUser Interaction
NoneScope
UnchangedConfidentiality
NoneIntegrity
NoneAvailability
HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
NVD Known Affected Configurations (CPE 2.3)
Vendor Declared Affected Products
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| github.com/free5gc/free5gc/issues/924 | 134c704f-9b21-4f2e-91b3-4a467353bcc0 | github.com | Exploit, Issue Tracking |
| github.com/free5gc/nef/pull/25 | [email protected] | github.com | Issue Tracking, Patch |
| github.com/free5gc/free5gc/security/advisories/GHSA-rxrq-fv76-26pr | 134c704f-9b21-4f2e-91b3-4a467353bcc0 | github.com | Exploit, Vendor Advisory |
| github.com/free5gc/nef/commit/f110517b1189801950b50668a593398687049074 | [email protected] | github.com | Patch |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
No vendor comments have been submitted for this CVE.
There are currently no legacy QID mappings associated with this CVE.