CVE-2026-44317

free5GC's PCF npcf-policyauthorization POST /app-sessions panics on suppFeat=1 with missing AfRoutReq via nil pointer dereference

NULL pointer dereference (CWE-476) caused by improper handling of an exceptional branch (CWE-754): the create path passes routeReq straight into provisioningOfTrafficRoutingInfo without a nil check, even though medComp.AfRoutReq is optional and is nil for the demonstrated valid input shape. The control experiment with suppFeat="0" proves the request shape itself is otherwise valid.

Gin recovery catches the panic, so the PCF process is NOT killed and other endpoints continue serving. The realized impact is per-request: any authenticated POST against this endpoint with suppFeat="1" and medComponents.*.AfAppId set but AfRoutReq absent returns HTTP 500 with empty body and a stack trace in PCF logs.

Any party that holds (or can obtain) a valid npcf-policyauthorization token can repeatedly drive this code path to sustain a per-request panic-DoS on the app-session create endpoint, with each panic costing more CPU + log writes than the intended controlled response would have.

No Confidentiality impact (the response is 500 with empty body). No persistent Integrity impact (the panic happens before any state mutation). Availability impact is limited to per-request degradation.

Affected: free5gc v4.2.1.

Upstream issue: https://github.com/free5gc/free5gc/issues/879
Upstream fix: https://github.com/free5gc/pcf/pull/65

The application dereferences a null pointer, causing a crash. Typical impact: denial of service via crash.

CVE-2026-44317 has a CVSS score of 6.5 (Medium). The vector is network-reachable, low privileges required, and no user interaction. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. A fixed version is available (1.4.3); upgrading removes the vulnerable code path.

Kodem intelligence

1. What is CVE-2026-44317? CVE-2026-44317 is a medium-severity null pointer dereference vulnerability in github.com/free5gc/pcf (go), affecting versions < 1.4.3. It is fixed in 1.4.3. The application dereferences a null pointer, causing a crash.
2. How severe is CVE-2026-44317? CVE-2026-44317 has a CVSS score of 6.5 (Medium). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
3. Which versions of github.com/free5gc/pcf are affected by CVE-2026-44317? github.com/free5gc/pcf (go) versions < 1.4.3 is affected.
4. Is there a fix for CVE-2026-44317? Yes. CVE-2026-44317 is fixed in 1.4.3. Upgrade to this version or later.
5. Is CVE-2026-44317 exploitable, and should I be worried? Whether CVE-2026-44317 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
6. What actually determines whether CVE-2026-44317 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
7. How do I fix CVE-2026-44317? Upgrade github.com/free5gc/pcf to 1.4.3 or later.