Use-after-free in Linux kernel qualcomm emac driver

1) Use-after-free

EUVDB-ID: #VU90103

Risk: Low

CVSSv4.0: 5.9 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2021-47311

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 emac_remove() function in drivers/net/ethernet/qualcomm/emac/emac.c. A local user can escalate privileges on the system.

Mitigation

Install update from vendor's website.

Vulnerable software versions

Linux kernel: 4.9 - 5.14 rc7

CPE2.3

• cpe:2.3:o:linux_foundation:linux_kernel:4.9:*:*:*:*:*:*:*
• cpe:2.3:o:linux_foundation:linux_kernel:4.9.0:*:*:*:*:*:*:*
• cpe:2.3:o:linux_foundation:linux_kernel:4.9.1:*:*:*:*:*:*:*
• cpe:2.3:o:linux_foundation:linux_kernel:4.9.2:*:*:*:*:*:*:*
• cpe:2.3:o:linux_foundation:linux_kernel:4.9.3:*:*:*:*:*:*:*
• cpe:2.3:o:linux_foundation:linux_kernel:4.9.4:*:*:*:*:*:*:*
• cpe:2.3:o:linux_foundation:linux_kernel:4.9.5:*:*:*:*:*:*:*
• cpe:2.3:o:linux_foundation:linux_kernel:4.9.6:*:*:*:*:*:*:*
• cpe:2.3:o:linux_foundation:linux_kernel:4.9.7:*:*:*:*:*:*:*
• cpe:2.3:o:linux_foundation:linux_kernel:4.9.8:*:*:*:*:*:*:*

External links

https://git.kernel.org/stable/c/4d04a42b926e682140776e54188f4a44f1f01a81
https://git.kernel.org/stable/c/b1e091331920f8fbfc747dcbd16263fcd71abb2d
https://git.kernel.org/stable/c/11e9d163d631198bb3eb41a677a61b499516c0f7
https://git.kernel.org/stable/c/2b70ca92847c619d6264c7372ef74fcbfd1e048c
https://git.kernel.org/stable/c/b560521eca03d0a2db6093a5a632cbdd0a0cf833
https://git.kernel.org/stable/c/8a225a6e07a57a1538d53637cb3d82bd3e477839
https://git.kernel.org/stable/c/ad297cd2db8953e2202970e9504cab247b6c7cb4
https://mirrors.edge.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.14.241
https://mirrors.edge.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.19.199
https://mirrors.edge.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.9.277
https://mirrors.edge.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.10.53
https://mirrors.edge.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.13.5
https://mirrors.edge.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.14
https://mirrors.edge.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.4.135

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.