CVE-2021-3671 Null dereference in Samba

What is CVE-2021-3671?

CVE-2021-3671 is a medium-severity vulnerability in Debian Debian Linux, published on 12 Oct 2021. Any signed-in user can exploit it over the network, with no action from the victim.

Official description

A null pointer de-reference was found in the way samba kerberos server handled missing sname in TGS-REQ (Ticket Granting Server - Request). An authenticated user could use this flaw to crash the samba server.

Weakness: CWE-476

Which versions are affected by CVE-2021-3671?

It affects 5 products.

Products include Debian Debian Linux, Netapp Management Services for Element Software, Netapp Management Services for Netapp Hci, Netapp Ontap Select Deploy Administration Utility, Samba Samba.

How do I fix CVE-2021-3671?

Apply the vendor's patch.

Is CVE-2021-3671 being exploited?

There is no known exploitation of CVE-2021-3671 in the wild and no public exploit code.

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All Debian Debian Linux vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as ALPINE-CVE-2021-3671, AZL-37004, AZL-7354, CLEANSTART-2024-NJ43669, DEBIAN-CVE-2021-3671, ECHO-f6d0-c68c-35ad and 4 more.