A shadow security update has been released for Ubuntu Linux 14.04 ESM, 16.04 ESM, 18.04 LTS, 20.04 LTS, 22.04 LTS, and 22.10.

USN-5745-1: shadow vulnerability

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Ubuntu Security Notice USN-5745-1
November 28, 2022

shadow vulnerability
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A security issue affects these releases of Ubuntu and its derivatives:

- Ubuntu 22.10
- Ubuntu 22.04 LTS
- Ubuntu 20.04 LTS
- Ubuntu 18.04 LTS
- Ubuntu 16.04 ESM
- Ubuntu 14.04 ESM

Summary:

shadow could be made to overwrite files.

Software Description:
- shadow: system login tools

Details:

Florian Weimer discovered that shadow was not properly copying and removing
user directory trees, which could lead to a race condition. A local attacker
could possibly use this issue to setup a symlink attack and alter or remove
directories without authorization.

Update instructions:

The problem can be corrected by updating your system to the following
package versions:

Ubuntu 22.10:
libsubid4 1:4.11.1+dfsg1-2ubuntu1.1
login 1:4.11.1+dfsg1-2ubuntu1.1
passwd 1:4.11.1+dfsg1-2ubuntu1.1
uidmap 1:4.11.1+dfsg1-2ubuntu1.1

Ubuntu 22.04 LTS:
login 1:4.8.1-2ubuntu2.1
passwd 1:4.8.1-2ubuntu2.1
uidmap 1:4.8.1-2ubuntu2.1

Ubuntu 20.04 LTS:
login 1:4.8.1-1ubuntu5.20.04.3
passwd 1:4.8.1-1ubuntu5.20.04.3
uidmap 1:4.8.1-1ubuntu5.20.04.3

Ubuntu 18.04 LTS:
login 1:4.5-1ubuntu2.4
passwd 1:4.5-1ubuntu2.4
uidmap 1:4.5-1ubuntu2.4

Ubuntu 16.04 ESM:
login 1:4.2-3.1ubuntu5.5+esm2
passwd 1:4.2-3.1ubuntu5.5+esm2
uidmap 1:4.2-3.1ubuntu5.5+esm2

Ubuntu 14.04 ESM:
login 1:4.1.5.1-1ubuntu9.5+esm2
passwd 1:4.1.5.1-1ubuntu9.5+esm2
uidmap 1:4.1.5.1-1ubuntu9.5+esm2

In general, a standard system update will make all the necessary changes.

References:
https://ubuntu.com/security/notices/USN-5745-1
CVE-2013-4235

Package Information:
https://launchpad.net/ubuntu/+source/shadow/1:4.11.1+dfsg1-2ubuntu1.1
https://launchpad.net/ubuntu/+source/shadow/1:4.8.1-2ubuntu2.1
https://launchpad.net/ubuntu/+source/shadow/1:4.8.1-1ubuntu5.20.04.3
https://launchpad.net/ubuntu/+source/shadow/1:4.5-1ubuntu2.4