#VU63734 Out-of-bounds write in AMD products - CVE-2021-26369

Vulnerability identifier: #VU63734

Vulnerability 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-2021-26369

CWE-ID: CWE-787

Exploitation vector: Local

Exploit availability: No

Vulnerable software:
AMD Ryzen 2000 series Desktop processor
Hardware solutions / Firmware
2nd Gen AMD Ryzen Threadripper processors
Hardware solutions / Firmware
AMD Ryzen 2000 Series Mobile processor
Hardware solutions / Firmware
AMD Ryzen 3000 Series Mobile processor
Hardware solutions / Firmware
2nd Gen AMD Ryzen Mobile processor with Radeon graphics
Hardware solutions / Firmware
AMD Athlon 3000 Series Mobile processors with Radeon Graphics
Hardware solutions / Firmware
AMD Ryzen 3000 Series Mobile processor with Radeon graphics
Hardware solutions / Firmware
AMD Ryzen 5000 Series Mobile processor with Radeon graphics
Hardware solutions / Firmware

Vendor: AMD

Description

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

The vulnerability exists due to a boundary error. A malicious or compromised UApp or ABL can send a malformed system call to the bootloader and escalate privileges on the system.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

AMD Ryzen 2000 series Desktop processor: All versions

2nd Gen AMD Ryzen Threadripper processors: All versions

AMD Ryzen 2000 Series Mobile processor: All versions

AMD Ryzen 3000 Series Mobile processor: All versions

2nd Gen AMD Ryzen Mobile processor with Radeon graphics: All versions

AMD Athlon 3000 Series Mobile processors with Radeon Graphics: All versions

AMD Ryzen 3000 Series Mobile processor with Radeon graphics: All versions

AMD Ryzen 5000 Series Mobile processor with Radeon graphics: All versions

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External links
https://www.amd.com/en/corporate/product-security/bulletin/amd-sb-1027

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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.