SB2021080813 - Denial of service in Linux kernel NFSv4 implementation
Published: August 8, 2021 Updated: March 9, 2022
Security Bulletin ID
SB2021080813
Severity
Low
Patch available
YES
Number of vulnerabilities
1
Exploitation vector
Adjecent network
Highest impact
Denial of service
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 1 security vulnerability.
1) Race condition (CVE-ID: CVE-2021-38199)
The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.
The vulnerability exists due to fs/nfs/nfs4client.c in the Linux kernel has incorrect connection-setup ordering. A remote attacker with access to a remote NFSv4 server can perform a denial of service (DoS) attack by arranging the server to be unreachable during trunking detection.
Remediation
Install update from vendor's website.
References
- https://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.13.4
- https://github.com/torvalds/linux/commit/dd99e9f98fbf423ff6d365b37a98e8879170f17c
- https://security.netapp.com/advisory/ntap-20210902-0010/
- https://www.debian.org/security/2021/dsa-4978
- https://lists.debian.org/debian-lts-announce/2021/10/msg00010.html
- https://lists.debian.org/debian-lts-announce/2021/12/msg00012.html