{"id":"CVE-2011-4120","url":"https://www.cyber-defence.io/tools/cve/CVE-2011-4120","generatedAt":"2026-10-27T21:03:44.397Z","title":"A remote attacker could use this flaw to circumvent common authentication process and obtain access to the account in question by providing a NULL value (pressing Ctrl-D keyboard sequence) as the password string.","description":"Yubico PAM Module before 2.10 performed user authentication when 'use_first_pass' PAM configuration option was not used and the module was configured as 'sufficient' in the PAM configuration. A remote attacker could use this flaw to circumvent common authentication process and obtain access to the account in question by providing a NULL value (pressing Ctrl-D keyboard sequence) as the password string.","published":"2019-11-26T05:15:13.000Z","lastModified":"2026-06-16T23:34:28.000Z","status":"Modified","sourceIdentifier":"secalert@redhat.com","cvss":{"version":"3.1","score":9.8,"severity":"CRITICAL","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"},"cwe":["CWE-20"],"affected":["yubico/pam module","debian/debian linux"],"epss":{"score":0.02019,"percentile":0.808,"date":"2026-10-26","history":[]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"high","text":"High impact if exploited, but EPSS currently rates exploitation as unlikely (2.02%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit."},"changes":[],"references":[{"url":"https://access.redhat.com/security/cve/cve-2011-4120","tags":["Broken Link","Third Party Advisory"],"source":"secalert@redhat.com"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2011-4120","tags":["Issue Tracking","Patch","Third Party Advisory"],"source":"secalert@redhat.com"},{"url":"https://security-tracker.debian.org/tracker/CVE-2011-4120","tags":["Third Party Advisory"],"source":"secalert@redhat.com"},{"url":"https://www.openwall.com/lists/oss-security/2011/11/07/6","tags":["Mailing List","Third Party Advisory"],"source":"secalert@redhat.com"},{"url":"https://access.redhat.com/security/cve/cve-2011-4120","tags":["Broken Link","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2011-4120","tags":["Issue Tracking","Patch","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://security-tracker.debian.org/tracker/CVE-2011-4120","tags":["Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://www.openwall.com/lists/oss-security/2011/11/07/6","tags":["Mailing List","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2011-4120","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}