{"id":"CVE-2020-27840","url":"https://www.cyber-defence.io/tools/cve/CVE-2020-27840","generatedAt":"2026-10-27T20:22:40.700Z","title":"Spaces used in a string around a domain name (DN), while supposed to be ignored, can cause invalid DN strings with spaces to instead write a zero-byte into out-of-bounds memory, resulting in a crash.","description":"A flaw was found in samba. Spaces used in a string around a domain name (DN), while supposed to be ignored, can cause invalid DN strings with spaces to instead write a zero-byte into out-of-bounds memory, resulting in a crash. The highest threat from this vulnerability is to system availability.","published":"2021-05-12T15:15:08.000Z","lastModified":"2026-06-17T03:09:43.000Z","status":"Modified","sourceIdentifier":"secalert@redhat.com","cvss":{"version":"3.1","score":7.5,"severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"},"cwe":["CWE-125"],"affected":["samba/samba","debian/debian linux","fedoraproject/fedora"],"epss":{"score":0.03833,"percentile":0.90023,"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 (3.83%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit."},"changes":[],"references":[{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=1941400","tags":["Issue Tracking","Third Party Advisory"],"source":"secalert@redhat.com"},{"url":"https://lists.debian.org/debian-lts-announce/2021/03/msg00036.html","tags":["Mailing List","Third Party Advisory"],"source":"secalert@redhat.com"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/VLZ74IF2N75VQSIHBL4B3P5WKWQCXSRY/","source":"secalert@redhat.com"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/X5J3B6PN5XMXF3OHYBNHDKZ3XFSUGY4L/","source":"secalert@redhat.com"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ZXP3ONIY6MB4C5LDZV4YL5KJCES3UX24/","source":"secalert@redhat.com"},{"url":"https://security.gentoo.org/glsa/202105-22","tags":["Third Party Advisory"],"source":"secalert@redhat.com"},{"url":"https://security.netapp.com/advisory/ntap-20210326-0007/","tags":["Third Party Advisory"],"source":"secalert@redhat.com"},{"url":"https://www.debian.org/security/2021/dsa-4884","tags":["Third Party Advisory"],"source":"secalert@redhat.com"},{"url":"https://www.samba.org/samba/security/CVE-2020-27840.html","tags":["Vendor Advisory"],"source":"secalert@redhat.com"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=1941400","tags":["Issue Tracking","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.debian.org/debian-lts-announce/2021/03/msg00036.html","tags":["Mailing List","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/VLZ74IF2N75VQSIHBL4B3P5WKWQCXSRY/","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/X5J3B6PN5XMXF3OHYBNHDKZ3XFSUGY4L/","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ZXP3ONIY6MB4C5LDZV4YL5KJCES3UX24/","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://security.gentoo.org/glsa/202105-22","tags":["Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://security.netapp.com/advisory/ntap-20210326-0007/","tags":["Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://www.debian.org/security/2021/dsa-4884","tags":["Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://www.samba.org/samba/security/CVE-2020-27840.html","tags":["Vendor Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2020-27840","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."}