free5GC's PCF npcf-smpolicycontrol POST /sm-policies panics on downstream UDR/OpenAPI 404 via nil pointer dereference

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

7.5 · CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

EPSS

• CVE-2026-44316: 0.40% estimated exploitation activity in the next 30 days; percentile 34.70 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

Summary 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 v4.2.1 this endpoint is also reachable WITHOUT an Authorization header because the PCF NpcfSMPolicyControl route group is mounted without inbound auth middleware (see free5gc/free5gc#844). So in the validation lab the trigger is fully…

Published by the source

8 May 2026, 22:39 UTC

Last modified by the source

8 Jun 2026, 23:47 UTC

Source last checked

26 Oct 2026, 15:23 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-wr8j-6chw-gm6p

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# Patch Next advisory brief: CVE-2026-44316

Advisory: free5GC's PCF npcf-smpolicycontrol POST /sm-policies panics on downstream UDR/OpenAPI 404 via nil pointer dereference
IDs: CVE-2026-44316, GHSA-wr8j-6chw-gm6p
Record: https://patchnext.com/advisories/cve-2026-44316 (revision 1, source checked 26 Oct 2026, 15:23 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: High (CVSS 7.5)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: github.com/free5gc/pcf 1.4.2. A vendor fix does not mean a deployment is fixed.

## Affected components
- Go github.com/free5gc/pcf: affected < 1.4.2; fixed in 1.4.2

## Suggested inspection (read-only)
- Go github.com/free5gc/pcf: check the installed version with your package manager.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on github.com/free5gc/pcf.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://github.com/advisories/GHSA-wr8j-6chw-gm6p (GitHub-reviewed advisory GHSA-wr8j-6chw-gm6p lists affected ranges: Go github.com/free5gc/pcf >=0 <1.4.2)

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