CVE-2021-20254

Description

A flaw was found in samba. The Samba smbd file server must map Windows group identities (SIDs) into unix group ids (gids). The code that performs this had a flaw that could allow it to read data beyond the end of the array in the case where a negative cache entry had been added to the mapping cache. This could cause the calling code to return those values into the process token that stores the group membership for a user. The highest threat from this vulnerability is to data confidentiality and integrity.

Category

6.8
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.66% Top 30%
Vendor Advisory fedoraproject.org Vendor Advisory fedoraproject.org Vendor Advisory gentoo.org Vendor Advisory samba.org
Affected: n/a samba
Published at:
Updated at:

References

Frequently Asked Questions

What is the severity of CVE-2021-20254?
CVE-2021-20254 has been scored as a medium severity vulnerability.
How to fix CVE-2021-20254?
To fix CVE-2021-20254, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-20254 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-20254 is being actively exploited. According to its EPSS score, there is a ~1% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-20254?
CVE-2021-20254 affects n/a samba.
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