Use-after-free in Linux kernel btrfs

1) Use-after-free

EUVDB-ID: #VU90256

Risk: Low

CVSSv3.1: 7.7 [AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2021-46958

CWE-ID: CWE-416 - Use After Free

Exploit availability: No

Description

The vulnerability allows a local user to escalate privileges on the system.

The vulnerability exists due to a use-after-free error within the cleanup_transaction() function in fs/btrfs/transaction.c. A local user can escalate privileges on the system.

Mitigation

Install update from vendor's website.

Vulnerable software versions

Linux kernel: All versions

CPE2.3

External links

http://git.kernel.org/stable/c/a4794be7b00b7eda4b45fffd283ab7d76df7e5d6
http://git.kernel.org/stable/c/633f7f216663587f17601eaa1cf2ac3d5654874c
http://git.kernel.org/stable/c/e2da98788369bfba1138bada72765c47989a4338
http://git.kernel.org/stable/c/061dde8245356d8864d29e25207aa4daa0be4d3c

Q & A

Can this vulnerability be exploited remotely?

No. This vulnerability can be exploited locally. The attacker should have authentication credentials and successfully authenticate on the system.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.