Use of uninitialized resource in Linux kernel - CVE-2021-47136
Published: June 10, 2024 / Updated: May 13, 2025
Vulnerability identifier: #VU91680
CSH Severity: Low
CVSS v4.0: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear
CVE-ID: CVE-2021-47136
CWE-ID: CWE-908
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vendor: Linux Foundation
Affected software:
Linux kernel
Linux kernel
Detailed vulnerability description
The vulnerability allows a local user to perform a denial of service (DoS) attack.
The vulnerability exists due to use of uninitialized resource within the tcf_classify_ingress() function in net/sched/cls_api.c, within the mlx5e_tc_update_skb() function in drivers/net/ethernet/mellanox/mlx5/core/en_tc.c, within the mlx5e_rep_tc_update_skb() function in drivers/net/ethernet/mellanox/mlx5/core/en/rep/tc.c. A local user can perform a denial of service (DoS) attack.
How to mitigate CVE-2021-47136
Install update from vendor's website.
Sources
- https://git.kernel.org/stable/c/ac493452e937b8939eaf2d24cac51a4804b6c20e
- https://git.kernel.org/stable/c/86ab133b695ed7ba1f8786b12f4ca43137ad8c18
- https://git.kernel.org/stable/c/9453d45ecb6c2199d72e73c993e9d98677a2801b
- https://mirrors.edge.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.10.42
- https://mirrors.edge.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.12.9
- https://mirrors.edge.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.13