CVE-2021-27239 Memory corruption in Multiple Routers
Network-adjacent attackers can execute arbitrary code as root on NETGEAR routers via a stack buffer overflow in the upnpd service.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2021-27239?
CVE-2021-27239 is a high-severity memory corruption vulnerability in Netgear D6220 Firmware, published on 29 Mar 2021. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
This vulnerability allows network-adjacent attackers to execute arbitrary code on affected installations of NETGEAR R6400 and R6700 firmware version 1.0.4.98 routers. Authentication is not required to exploit this vulnerability. The specific flaw exists within the upnpd service, which listens on UDP port 1900 by default. A crafted MX header field in an SSDP message can trigger an overflow of a fixed-length stack-based buffer. An attacker can leverage this vulnerability to execute code in the context of root. Was ZDI-CAN-11851.
Weakness: CWE-121
Which versions are affected by CVE-2021-27239?
It affects 35 products.
Products include Netgear D6220 Firmware, Netgear D6400 Firmware, Netgear D7000 Firmware, Netgear D8500 Firmware, Netgear Dc112a Firmware, Netgear Ex7000 Firmware and 29 more.
How do I fix CVE-2021-27239?
No fix has been published for CVE-2021-27239 yet. Limit exposure of the affected software until one is available.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2021-27239 being exploited?
There is no known exploitation of CVE-2021-27239 in the wild and no public exploit code.
Other vulnerabilities in Netgear D6220 Firmware
Sources
Also known as GHSA-hqww-3wrx-q5gv.