Is CVE-2026-44319 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-44319 being exploited in the wild.

How severe is CVE-2026-44319?

High severity, with a CVSS score of 7.5, published 27 May 2026.

Which products and versions are affected?

free5GC NEF < 1.2.3, <= v4.2.1; github.com/free5gc/nef (Go) < 1.2.3, SEMVER:introduced=0,fixed=1.2.3.

Is there a fix for CVE-2026-44319?

Yes. github.com/free5gc/nef (Go): upgrade to 1.2.3 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-44319 attacked?

It is attacked over the network, in a hosted service.

Am I affected by CVE-2026-44319?

Check whether you run free5GC NEF or github.com/free5gc/nef (Go) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-44319: free5GC NEF denial of service via unreachable notification URI

Q: Which products and versions are affected?

free5GC NEF < 1.2.3, <= v4.2.1; github.com/free5gc/nef (Go) < 1.2.3, SEMVER:introduced=0,fixed=1.2.3.

Q: Is there a fix for CVE-2026-44319?

Yes. github.com/free5gc/nef (Go): upgrade to 1.2.3 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

Q: How is CVE-2026-44319 attacked?

It is attacked over the network, in a hosted service.

Q: Am I affected by CVE-2026-44319?

Check whether you run free5GC NEF or github.com/free5gc/nef (Go) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-44319 · Severity: high · CVSS 7.5 · Published 2026-05-27

The Network Exposure Function (NEF) in free5GC, which allows external applications to interact with the 5G core network, contains a flaw that causes the entire service to shut down. An attacker can provide a malformed or unreachable notification address that, when triggered, forces the NEF process to terminate immediately. This results in a complete loss of service availability, preventing external applications from communicating with the mobile core until the system is manually restarted.

Technologies: free5GC NEF, github.com/free5gc/nef (Go). Vendors: free5GC, Go.

Quick answers

Is CVE-2026-44319 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-44319 being exploited in the wild.
How severe is CVE-2026-44319?: High severity, with a CVSS score of 7.5, published 27 May 2026.
Which products and versions are affected?: free5GC NEF < 1.2.3, <= v4.2.1; github.com/free5gc/nef (Go) < 1.2.3, SEMVER:introduced=0,fixed=1.2.3.
Is there a fix for CVE-2026-44319?: Yes. github.com/free5gc/nef (Go): upgrade to 1.2.3 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-44319 attacked?: It is attacked over the network, in a hosted service.
Am I affected by CVE-2026-44319?: Check whether you run free5GC NEF or github.com/free5gc/nef (Go) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

github.com/free5gc/nef (Go): upgrade to 1.2.3 or later
```
go get github.com/free5gc/nef@v1.2.3
```

Technical details

A denial-of-service vulnerability exists in the free5GC NEF component due to improper error handling in the PFD notification path. In `PfdChangeNotifier.FlushNotifications()`, the application invokes `logger.PFDManageLog.Fatal(err)` upon any delivery failure to a subscriber's `notifyUri`. In Go, the `Fatal` log level triggers an immediate `os.Exit(1)`, bypassing standard middleware recovery mechanisms. An unauthenticated attacker can exploit this by creating a PFD subscription with an unreachable URI and triggering a PFD change, causing the NEF process to crash. This is fixed in version 1.2.3 of the NEF component.

Affected products

free5GC nef < 1.2.3

Identifiers

CVE-2026-44319
GHSA-rxrq-fv76-26pr
GO-2026-5647

Timeline

2026-03-20: other: Vulnerability validated in lab environment
2026-05-08: advisory
2026-05-27: disclosed: NVD publication date

References

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