CVE-2020-27840

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.

• CWE-125

• https://bugzilla.redhat.com/show_bug.cgi?id=1941400Issue Tracking, Third Party Advisory
• https://lists.debian.org/debian-lts-announce/2021/03/msg00036.htmlMailing List, Third Party Advisory
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/VLZ74IF2N75VQSIHBL4B3P5WKWQCXSRY/
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/X5J3B6PN5XMXF3OHYBNHDKZ3XFSUGY4L/
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ZXP3ONIY6MB4C5LDZV4YL5KJCES3UX24/
• https://security.gentoo.org/glsa/202105-22Third Party Advisory
• https://security.netapp.com/advisory/ntap-20210326-0007/Third Party Advisory
• https://www.debian.org/security/2021/dsa-4884Third Party Advisory
• https://www.samba.org/samba/security/CVE-2020-27840.htmlVendor Advisory
• https://bugzilla.redhat.com/show_bug.cgi?id=1941400Issue Tracking, Third Party Advisory
• https://lists.debian.org/debian-lts-announce/2021/03/msg00036.htmlMailing List, Third Party Advisory
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/VLZ74IF2N75VQSIHBL4B3P5WKWQCXSRY/
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/X5J3B6PN5XMXF3OHYBNHDKZ3XFSUGY4L/
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ZXP3ONIY6MB4C5LDZV4YL5KJCES3UX24/
• https://security.gentoo.org/glsa/202105-22Third Party Advisory
• https://security.netapp.com/advisory/ntap-20210326-0007/Third Party Advisory
• https://www.debian.org/security/2021/dsa-4884Third Party Advisory
• https://www.samba.org/samba/security/CVE-2020-27840.htmlVendor Advisory

Published

May 12, 2021

Last Modified

Jun 17, 2026

Status

Modified

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