High severity · published May 12, 2021
CVE-2020-27840
A flaw was found in samba
7.5
CVSS
3.8%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)3.8% · higher than 90% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
DL
Debian Linux · Debian
9.0; 10.0 · source: NVD
FE
Fedora · Fedoraproject
32; 33; 34 · source: NVD
SA
Samba · Samba
4.0.0 before 4.12.13; 4.13.0 before 4.13.6; 4.14.0 before 4.14.1 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2020-27840
CVE.org
https://www.cve.org/CVERecord?id=CVE-2020-27840
Issue Tracking
https://bugzilla.redhat.com/show_bug.cgi?id=1941400
Mailing List
https://lists.debian.org/debian-lts-announce/2021/03/msg00036.html
lists.fedoraproject.org
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/VLZ74IF2N75VQSIHBL4B3P5WKWQCXSRY/
lists.fedoraproject.org
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/X5J3B6PN5XMXF3OHYBNHDKZ3XFSUGY4L/
lists.fedoraproject.org
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ZXP3ONIY6MB4C5LDZV4YL5KJCES3UX24/
Third Party Advisory
https://security.gentoo.org/glsa/202105-22
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