{"id":"CVE-2019-19521","aliases":["EUVD-2019-9139","GHSA-gw7q-976q-g767"],"status":"published","title":"libc in OpenBSD 6.6 allows authentication bypass via the -schallenge username, as demonstrated by...","description":"libc in OpenBSD 6.6 allows authentication bypass via the -schallenge username, as demonstrated by smtpd, ldapd, or radiusd. This is related to gen/auth_subr.c and gen/authenticate.c in libc (and login/login.c and xenocara/app/xenodm/greeter/verify.c).","severity":{"version":"3.1","score":9.8,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","level":"critical","assessor":"primary","from":"nvd"},"epss":{"day":"2026-11-10","score":0.02736,"percentile":0.86241,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-287"],"published":"2019-12-04T23:33:35Z","modified":"2026-06-17T02:26:48Z","products":[{"vendor":"openbsd","product":"openbsd"}],"references":[{"url":"https://www.openwall.com/lists/oss-security/2019/12/04/5","tags":["x_refsource_MISC","x_transferred","Exploit","Mailing List","Third Party Advisory"]},{"url":"https://www.openbsd.org/errata66.html","tags":["x_refsource_MISC","x_transferred","Vendor Advisory"]},{"url":"http://www.openwall.com/lists/oss-security/2019/12/04/6","tags":["mailing-list","x_refsource_MLIST","x_transferred","Mailing List"]},{"url":"http://www.openwall.com/lists/oss-security/2019/12/04/5","tags":["mailing-list","x_refsource_MLIST","x_transferred","Exploit","Mailing List","Third Party Advisory"]},{"url":"https://seclists.org/bugtraq/2019/Dec/8","tags":["mailing-list","x_refsource_BUGTRAQ","x_transferred","Exploit","Mailing List","Third Party Advisory"]},{"url":"http://packetstormsecurity.com/files/155572/Qualys-Security-Advisory-OpenBSD-Authentication-Bypass-Privilege-Escalation.html","tags":["x_refsource_MISC","x_transferred","Third Party Advisory"]},{"url":"http://seclists.org/fulldisclosure/2019/Dec/14","tags":["mailing-list","x_refsource_FULLDISC","x_transferred","Third Party Advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2019-19521"},{"url":"https://github.com/advisories/GHSA-gw7q-976q-g767"}],"sources":{"cve":[{"id":"CVE-2019-19521","description":"libc in OpenBSD 6.6 allows authentication bypass via the -schallenge username, as demonstrated by smtpd, ldapd, or radiusd. This is related to gen/auth_subr.c and gen/authenticate.c in libc (and login/login.c and xenocara/app/xenodm/greeter/verify.c).","status":"published","published":"2019-12-04T23:33:35Z","modified":"2024-08-05T02:16:47.981Z","updated_at":"2026-11-02T14:20:20.74896Z"}],"euvd":[{"id":"EUVD-2019-9139","description":"libc in OpenBSD 6.6 allows authentication bypass via the -schallenge username, as demonstrated by smtpd, ldapd, or radiusd. This is related to gen/auth_subr.c and gen/authenticate.c in libc (and login/login.c and xenocara/app/xenodm/greeter/verify.c).","status":"published","published":"2019-12-04T23:33:35Z","modified":"2024-08-05T02:16:47Z","updated_at":"2026-11-03T02:40:25.391321Z"}],"ghsa":[{"id":"GHSA-gw7q-976q-g767","title":"libc in OpenBSD 6.6 allows authentication bypass via the -schallenge username, as demonstrated by...","description":"libc in OpenBSD 6.6 allows authentication bypass via the -schallenge username, as demonstrated by smtpd, ldapd, or radiusd. This is related to gen/auth_subr.c and gen/authenticate.c in libc (and login/login.c and xenocara/app/xenodm/greeter/verify.c).","status":"published","published":"2022-05-24T17:02:43Z","modified":"2024-04-04T02:41:58Z","cvss":[{"version":"3.1","score":9.8,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","level":"critical"}],"cwes":["CWE-287"],"updated_at":"2026-11-02T14:56:11.047077Z"}],"nvd":[{"id":"CVE-2019-19521","description":"libc in OpenBSD 6.6 allows authentication bypass via the -schallenge username, as demonstrated by smtpd, ldapd, or radiusd. This is related to gen/auth_subr.c and gen/authenticate.c in libc (and login/login.c and xenocara/app/xenodm/greeter/verify.c).","status":"published","published":"2019-12-05T00:15:11.4Z","modified":"2026-06-17T02:26:48.05Z","cvss":[{"version":"3.1","score":9.8,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","level":"critical","assessor":"primary"},{"version":"2.0","score":7.5,"vector":"AV:N/AC:L/Au:N/C:P/I:P/A:P","level":"high","assessor":"primary"}],"cwes":["CWE-287"],"updated_at":"2026-11-02T14:05:38.993437Z"}]}}