#VU59236 Stack-based buffer overflow in SonicOS - CVE-2021-20048

Vulnerability identifier: #VU59236

Vulnerability risk: High

CVSSv4.0: 8.1 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Amber]

CVE-ID: CVE-2021-20048

CWE-ID: CWE-121

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
SonicOS
Operating systems & Components / Operating system

Vendor: SonicWall

Description

The vulnerability allows a remote attacker to execute arbitrary code on the target system.

The vulnerability exists due to a boundary error when processing SessionID HTTP response header. A remote unauthenticated attacker can send a specially HTTP response, trigger a stack-based buffer overflow and execute arbitrary code on the target system.

Successful exploitation of this vulnerability may result in complete compromise of vulnerable system.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

SonicOS: 5.9 - 7.0.1-5023-1349

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External links
https://psirt.global.sonicwall.com/vuln-detail/SNWLID-2021-0028

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

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