CVE-2020-27840

Publication date 24 March 2021

Last updated 24 July 2024

Ubuntu priority

Cvss 3 Severity Score

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.

Read the notes from the security team

Status

Show unmaintained releases

Package	Ubuntu Release	Status
ldb	20.10 groovy	Fixed 2:2.1.4-2ubuntu0.1
	20.04 LTS focal	Fixed 2:2.0.10-0ubuntu0.20.04.3
	18.04 LTS bionic	Fixed 2:1.2.3-1ubuntu0.2
	16.04 LTS xenial	Fixed 2:1.1.24-1ubuntu3.2
	14.04 LTS trusty	Fixed 1:1.1.24-0ubuntu0.14.04.2+esm1
samba	20.10 groovy	Not affected
	20.04 LTS focal	Not affected
	18.04 LTS bionic	Not affected
	16.04 LTS xenial	Not affected
	14.04 LTS trusty	Not affected

Get expanded security coverage with Ubuntu Pro

Reduce your average CVE exposure time from 98 days to 1 day with expanded CVE patching, ten-years security maintenance and optional support for the full stack of open-source applications. Free for personal use.

Get Ubuntu Pro 30-day free trial

Notes

mdeslaur

This issue is actually in the ldb package, the samba package uses the system ldb library, not the included one

Patch details

For informational purposes only. We recommend not to cherry-pick updates. How can I get the fixes?

Package	Patch details
ldb	Upstream: https://bugzilla.samba.org/attachment.cgi?id=16460 Upstream: https://bugzilla.samba.org/attachment.cgi?id=16462 Upstream: https://bugzilla.samba.org/attachment.cgi?id=16463 Upstream: https://bugzilla.samba.org/attachment.cgi?id=16464
samba	Upstream: https://bugzilla.samba.org/attachment.cgi?id=16460 Upstream: https://bugzilla.samba.org/attachment.cgi?id=16462 Upstream: https://bugzilla.samba.org/attachment.cgi?id=16463 Upstream: https://bugzilla.samba.org/attachment.cgi?id=16464

Severity score breakdown

Parameter	Value
Base score	7.5 · High
Attack vector	Network
Attack complexity	Low
Privileges required	None
User interaction	None
Scope	Unchanged
Confidentiality	None
Integrity impact	None
Availability impact	High
Vector	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H