#VU55591 Command Injection in OpenWrt - CVE-2021-28961

Vulnerability identifier: #VU55591

Vulnerability risk: Medium

CVSSv4.0: 6.3 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2021-28961

CWE-ID: CWE-77

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
OpenWrt
Operating systems & Components / Operating system

Vendor: openwrt.org

Description

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

The vulnerability exists due to improper input validation in the applications/luci-app-ddns/luasrc/model/cbi/ddns/detail.lua in the DDNS package. A remote authenticated attacker can pass specially crafted data to the application and execute arbitrary commands 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

OpenWrt: 19.07.0 - 19.07.7

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External links
https://github.com/openwrt/luci/commit/9df7ea4d66644df69fcea18b36bc465912ffc
https://openwrt.org/advisory/2021-08-01-3

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote authenticated user via the Internet.

Is there known malware, which exploits this vulnerability?

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