{"id":"CVE-2026-33063","aliases":["GHSA-4jrw-92fg-4jwx","GO-2026-4754"],"url":"https://o3.security/vulnerability/CVE-2026-33063","summary":"free5GC AUSF UE Authentication Panic on Nil SuciSupiMap Interface Conversion","details":"**Impact**  \nThis is an Improper Null Check vulnerability leading to Denial of Service.  \n- **Security Impact**: A remote attacker can cause the AUSF service to panic and crash by sending a crafted UE authentication request that triggers a nil interface conversion in the `GetSupiFromSuciSupiMap` function. This results in complete denial of service for the AUSF authentication service.  \n- **Functional Impact**: The `GetSupiFromSuciSupiMap` function attempts to perform an interface conversion from `interface{}` to `*context.SuciSupiMap` without checking if the underlying value is nil. When `SuciSupiMap` is nil, the code panics with \"interface conversion: interface {} is nil, not *context.SuciSupiMap\".  \n- **Affected Parties**: All deployments of free5GC v4.0.1 using the AUSF UE authentication service (`/nausf-auth/v1/ue-authentications` endpoint).\n\n**Patches**  \nYes, the issue has been patched.  \nThe fix is implemented in PR free5gc/ausf#52 (commit: [add specific commit hash if available]).  \nUsers should upgrade to the next release of free5GC that includes this commit.\n\n**Workarounds**  \nThere is no direct workaround at the application level. The recommendation is to apply the provided patch or restrict access to the AUSF API to trusted sources only.","published":"2026-03-20T02:53:28.186Z","modified":"2026-10-28T02:30:40.357730489Z","cvss":null,"epss":{"score":0.00652,"percentile":0.49528,"asOf":"2026-09-16"},"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"Go","name":"github.com/free5gc/ausf","fixedVersion":"1.4.2"}],"fix":{"url":"https://github.com/free5gc/ausf/commit/3b9ac4403c2756dc89a5ed3cdcefe688458588aa","label":"free5gc/ausf@3b9ac44"},"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/33xxx/CVE-2026-33063.json"},{"type":"ADVISORY","url":"https://github.com/free5gc/free5gc/security/advisories/GHSA-4jrw-92fg-4jwx"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-33063"},{"type":"REPORT","url":"https://github.com/free5gc/free5gc/issues/778"},{"type":"FIX","url":"https://github.com/free5gc/ausf/commit/3b9ac4403c2756dc89a5ed3cdcefe688458588aa"},{"type":"FIX","url":"https://github.com/free5gc/ausf/pull/52"},{"type":"PACKAGE","url":"https://github.com/free5gc/free5gc"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-10-28T02:30:40.357730489Z"}}