CVE-2021-43566

Description

All versions of Samba prior to 4.13.16 are vulnerable to a malicious client using an SMB1 or NFS race to allow a directory to be created in an area of the server file system not exported under the share definition. Note that SMB1 has to be enabled, or the share also available via NFS in order for this attack to succeed.

CVSS Metrics

• v3.1•LOW•Score: 2.5CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:L/A:N
• v2.0•LOW•Score: 1.2AV:L/AC:H/Au:N/C:N/I:P/A:N

EPSS Trends

Current EPSS score: 0.36%• Percentile: 59%

Techniques & Countermeasures

• CWE-362•Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')

  The product contains a concurrent code sequence that requires temporary, exclusive access to a shared resource, but a timing window exists in which the shared resource can be modified by another code sequence operating concurrently.

Affected Systems

• samba•samba

  < 4.13.16

References (3)

• https://bugzilla.samba.org/show_bug.cgi?id=13979
• https://security.netapp.com/advisory/ntap-20220110-0001/
• https://www.samba.org/samba/security/CVE-2021-43566.html