Vulnerability identifier: #VU90105

Vulnerability 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-2021-47321

CWE-ID: CWE-416

Exploitation vector: Local

Exploit availability: No

Vulnerable software:
Linux kernel
Operating systems & Components / Operating system

Vendor: Linux Foundation

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 wdt_startup() function in drivers/watchdog/w83877f_wdt.c, within the lpc18xx_wdt_remove() function in drivers/watchdog/lpc18xx_wdt.c. A local user can escalate privileges on the system.

Mitigation
Install update from vendor's website.

Vulnerable software versions

Linux kernel:

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External links
http://git.kernel.org/stable/c/58606882ad8ec6c39e0f40344b922921ef94ab4d
http://git.kernel.org/stable/c/ca96b8ea5e74956071154bdb456778cc3027e79f
http://git.kernel.org/stable/c/8bec568d7518b1504a602ed5376bb322e4dbb270
http://git.kernel.org/stable/c/ecd620e0fb1ff7f78fdb593379b2e6938c99707a
http://git.kernel.org/stable/c/db222f1477ad5692cd454709b714949807e5d111
http://git.kernel.org/stable/c/66ba9cf929b1c4fabf545bd4c18f6f64e23e46e4
http://git.kernel.org/stable/c/4c05dac488a660fe2925c047ecb119e7afaaeb1e
http://git.kernel.org/stable/c/1a053c4d716898a53c2e31c574a70ea0c37044a3
http://git.kernel.org/stable/c/d0212f095ab56672f6f36aabc605bda205e1e0bf

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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.