This vulnerability allows network-adjacent attackers to execute arbitrary code on affected installations of NETGEAR Nighthawk R7800. Authentication is not required to exploit this vulnerability The specific flaw exists within handling of firmware updates. The issue results from a fallback to a insecure protocol to deliver updates. An attacker can leverage this vulnerability to execute code in the context of root. Was ZDI-CAN-12308.

References

• https://nvd.nist.gov/vuln/detail/CVE-2021-27251
• https://kb.netgear.com/000062883/Security-Advisory-for-Multiple-Vulnerabilities-on-Some-Routers-Satellites-and-Extenders
• https://www.zerodayinitiative.com/advisories/ZDI-21-247/