CVE-2026-44316 is a high-severity (CVSS 7.5) vulnerability in github.com/free5gc/pcf. O3 Security confirms whether CVE-2026-44316 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
free5GC: PCF npcf-smpolicycontrol POST /sm-policies panics on downstream UDR/OpenAPI 404 via nil pointer dereference
Real-World Exposure
github.com/free5gc/pcfReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Go packages — download data is not available via public APIs for these ecosystems.
Description
free5GC is an open-source implementation of the 5G core network. Prior to 4.2.2, free5GC's PCF POST /npcf-smpolicycontrol/v1/sm-policies handler (HandleCreateSmPolicyRequest) panics with a nil-pointer dereference when a downstream OpenAPI consumer call (UDR lookup) returns 404 Not Found and the consumer wrapper returns err != nil together with a nil response struct. The handler logs the OpenAPI error and continues executing instead of returning, then dereferences the nil response struct on a subsequent line and panics. Gin recovery converts the panic into HTTP 500, so a single attacker-shaped POST returns 500 instead of a clean 4xx whenever the downstream lookup fails. The PCF process keeps running. The trigger is a single POST containing input that causes the downstream UDR lookup to fail (e.g. an unknown DNN). In 4.2.1 this endpoint is also reachable WITHOUT an Authorization header because the PCF Npcf_SMPolicyControl route group is mounted without inbound auth middleware. This vulnerability is fixed in 4.2.2.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | github.com/free5gc/pcf | all versions | 1.4.2 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/free5gc/pcf. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update github.com/free5gc/pcf to 1.4.2 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-44316 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether CVE-2026-44316 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to CVE-2026-44316. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2026-44316 in your dependencies?
O3 detects CVE-2026-44316 across Go dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.