{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-55785","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","state":"PUBLISHED","assignerShortName":"GitHub_M","dateReserved":"2026-06-17T14:40:28.380Z","datePublished":"2026-08-28T22:25:06.814Z","dateUpdated":"2026-08-28T22:25:06.814Z"},"containers":{"cna":{"title":"free5GC AUSF uses non-constant-time authentication comparisons and logs XRES* in 5G-AKA","problemTypes":[{"descriptions":[{"cweId":"CWE-208","lang":"en","description":"CWE-208: Observable Timing Discrepancy","type":"CWE"}]},{"descriptions":[{"cweId":"CWE-385","lang":"en","description":"CWE-385: Covert Timing Channel","type":"CWE"}]},{"descriptions":[{"cweId":"CWE-532","lang":"en","description":"CWE-532: Insertion of Sensitive Information into Log File","type":"CWE"}]}],"metrics":[{"cvssV3_1":{"attackComplexity":"HIGH","attackVector":"NETWORK","availabilityImpact":"NONE","baseScore":3.7,"baseSeverity":"LOW","confidentialityImpact":"LOW","integrityImpact":"NONE","privilegesRequired":"NONE","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N","version":"3.1"}}],"references":[{"name":"https://github.com/free5gc/free5gc/security/advisories/GHSA-fp46-6vfw-gc9c","tags":["x_refsource_CONFIRM"],"url":"https://github.com/free5gc/free5gc/security/advisories/GHSA-fp46-6vfw-gc9c"},{"name":"https://github.com/free5gc/ausf/pull/63","tags":["x_refsource_MISC"],"url":"https://github.com/free5gc/ausf/pull/63"},{"name":"https://github.com/free5gc/ausf/commit/7a5a4aa1ec6cd0e1febebf333911c3104968edf0","tags":["x_refsource_MISC"],"url":"https://github.com/free5gc/ausf/commit/7a5a4aa1ec6cd0e1febebf333911c3104968edf0"},{"name":"https://github.com/free5gc/ausf/releases/tag/v1.4.5","tags":["x_refsource_MISC"],"url":"https://github.com/free5gc/ausf/releases/tag/v1.4.5"}],"affected":[{"vendor":"free5gc","product":"free5gc","versions":[{"version":"< 1.4.5","status":"affected"}]}],"providerMetadata":{"orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","shortName":"GitHub_M","dateUpdated":"2026-08-28T22:25:06.814Z"},"descriptions":[{"lang":"en","value":"free5GC is an open-source implementation of the 5G core network. Prior to 1.4.5, the AUSF component performs cryptographic authentication comparisons in internal/sbi/processor/ue_authentication.go with ordinary equality helpers. Auth5gAkaComfirmRequestProcedure compares RES* and XRES* with strings.EqualFold and logs the expected XRES* value at INFO level before comparison. EapAuthComfirmRequestProcedure compares AT_MAC and XMAC with bytes.Equal and evaluates XRES == RES with ordinary string equality. These comparisons can return at mismatch-dependent times, although testing did not demonstrate a practical remote timing oracle because of HTTP/SBI timing noise. The INFO log exposes authentication material to operators, log collectors, sidecars, or processes able to read AUSF logs. This issue is fixed in version 1.4.5."}],"source":{"advisory":"GHSA-fp46-6vfw-gc9c","discovery":"UNKNOWN"}}}}