{"api_version":"1","generated_at":"2026-08-29T03:56:18+00:00","cve":"CVE-2026-55785","urls":{"html":"https://cve.report/CVE-2026-55785","api":"https://cve.report/api/cve/CVE-2026-55785.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-55785","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-55785"},"summary":{"title":"free5GC AUSF uses non-constant-time authentication comparisons and logs XRES* in 5G-AKA","description":"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.","state":"PUBLISHED","assigner":"GitHub_M","published_at":"2026-08-28 23:17:07","updated_at":"2026-08-28 23:17:07"},"problem_types":["CWE-208","CWE-385","CWE-532","CWE-208 CWE-208: Observable Timing Discrepancy","CWE-385 CWE-385: Covert Timing Channel","CWE-532 CWE-532: Insertion of Sensitive Information into Log File"],"metrics":[{"version":"3.1","source":"security-advisories@github.com","type":"Secondary","score":"3.7","severity":"LOW","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N","data":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N","baseScore":3.7,"baseSeverity":"LOW","attackVector":"NETWORK","attackComplexity":"HIGH","privilegesRequired":"NONE","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"LOW","integrityImpact":"NONE","availabilityImpact":"NONE"}},{"version":"3.1","source":"CNA","type":"DECLARED","score":"3.7","severity":"LOW","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N","data":{"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":[{"url":"https://github.com/free5gc/ausf/pull/63","name":"https://github.com/free5gc/ausf/pull/63","refsource":"security-advisories@github.com","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://github.com/free5gc/free5gc/security/advisories/GHSA-fp46-6vfw-gc9c","name":"https://github.com/free5gc/free5gc/security/advisories/GHSA-fp46-6vfw-gc9c","refsource":"security-advisories@github.com","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://github.com/free5gc/ausf/commit/7a5a4aa1ec6cd0e1febebf333911c3104968edf0","name":"https://github.com/free5gc/ausf/commit/7a5a4aa1ec6cd0e1febebf333911c3104968edf0","refsource":"security-advisories@github.com","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://github.com/free5gc/ausf/releases/tag/v1.4.5","name":"https://github.com/free5gc/ausf/releases/tag/v1.4.5","refsource":"security-advisories@github.com","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-55785","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-55785","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"free5gc","product":"free5gc","version":"affected < 1.4.5","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":null,"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"cna":{"affected":[{"product":"free5gc","vendor":"free5gc","versions":[{"status":"affected","version":"< 1.4.5"}]}],"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."}],"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"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-208","description":"CWE-208: Observable Timing Discrepancy","lang":"en","type":"CWE"}]},{"descriptions":[{"cweId":"CWE-385","description":"CWE-385: Covert Timing Channel","lang":"en","type":"CWE"}]},{"descriptions":[{"cweId":"CWE-532","description":"CWE-532: Insertion of Sensitive Information into Log File","lang":"en","type":"CWE"}]}],"providerMetadata":{"dateUpdated":"2026-08-28T22:25:06.814Z","orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","shortName":"GitHub_M"},"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"}],"source":{"advisory":"GHSA-fp46-6vfw-gc9c","discovery":"UNKNOWN"},"title":"free5GC AUSF uses non-constant-time authentication comparisons and logs XRES* in 5G-AKA"}},"cveMetadata":{"assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","assignerShortName":"GitHub_M","cveId":"CVE-2026-55785","datePublished":"2026-08-28T22:25:06.814Z","dateReserved":"2026-06-17T14:40:28.380Z","dateUpdated":"2026-08-28T22:25:06.814Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-08-28 23:17:07","lastModifiedDate":"2026-08-28 23:17:07","problem_types":["CWE-208","CWE-385","CWE-532","CWE-208 CWE-208: Observable Timing Discrepancy","CWE-385 CWE-385: Covert Timing Channel","CWE-532 CWE-532: Insertion of Sensitive Information into Log File"],"metrics":{"cvssMetricV31":[{"source":"security-advisories@github.com","type":"Secondary","cvssData":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N","baseScore":3.7,"baseSeverity":"LOW","attackVector":"NETWORK","attackComplexity":"HIGH","privilegesRequired":"NONE","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"LOW","integrityImpact":"NONE","availabilityImpact":"NONE"},"exploitabilityScore":2.2,"impactScore":1.4}]},"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"55785","Ordinal":"1","Title":"free5GC AUSF uses non-constant-time authentication comparisons a","CVE":"CVE-2026-55785","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"55785","Ordinal":"1","NoteData":"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.","Type":"Description","Title":"free5GC AUSF uses non-constant-time authentication comparisons a"}]}}}