{"schema_version":"1.7.5","id":"GHSA-958m-gxmc-mccm","published":"2026-03-18T20:07:17Z","modified":"2026-03-23T18:56:20.495758Z","aliases":["CVE-2026-33065","GO-2026-4758"],"summary":"free5GC UDM incorrectly returns 500 for empty supi path parameter in DELETE sdm-subscriptions request","details":"**Impact**  \nThis is an Improper Error Handling  vulnerability with Information Exposure implications.  \n- **Security Impact**: The UDM incorrectly converts a downstream 400 Bad Request (from UDR) into a 500 Internal Server Error when handling DELETE requests with an empty `supi` path parameter. This leaks internal error handling behavior and makes it difficult for clients to distinguish between client-side errors and server-side failures.  \n- **Functional Impact**: When a client sends a DELETE request with an empty `supi` (e.g., double slashes `//` in URL path), the UDM forwards the malformed request to UDR, which correctly returns 400. However, UDM propagates this as 500 SYSTEM_FAILURE instead of returning the appropriate 400 error to the client. This violates REST API best practices for DELETE operations.  \n- **Affected Parties**: All deployments of free5GC v4.0.1 using the UDM Nudm_SDM service with DELETE operations on sdm-subscriptions endpoint.\n\n**Patches**  \nYes, the issue has been patched.  \nThe fix is implemented in PR free5gc/udm#79.  \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 implement API gateway-level validation to reject DELETE requests with empty path parameters before they reach UDM.","affected":[{"package":{"name":"github.com/free5gc/udm","ecosystem":"Go","purl":"pkg:golang/github.com/free5gc/udm"},"ranges":[{"type":"SEMVER","events":[{"introduced":"0"},{"fixed":"1.4.2"}]}],"database_specific":{"source":"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/03/GHSA-958m-gxmc-mccm/GHSA-958m-gxmc-mccm.json"}}],"references":[{"type":"WEB","url":"https://github.com/free5gc/free5gc/security/advisories/GHSA-958m-gxmc-mccm"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-33065"},{"type":"WEB","url":"https://github.com/free5gc/free5gc/issues/783"},{"type":"WEB","url":"https://github.com/free5gc/udm/pull/79"},{"type":"WEB","url":"https://github.com/free5gc/udm/commit/88de9fa74a1b3f3522e53b4cfa2d184712ffa4ee"},{"type":"PACKAGE","url":"https://github.com/free5gc/free5gc"}],"database_specific":{"cwe_ids":["CWE-209"],"github_reviewed":true,"github_reviewed_at":"2026-03-18T20:07:17Z","nvd_published_at":"2026-03-20T08:16:12Z","severity":"MODERATE"},"severity":[{"type":"CVSS_V4","score":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N"}]}