Remote code execution in Multiple NETGEAR Routers

1) Stack-based buffer overflow

EUVDB-ID: #VU50953

Risk: Medium

CVSSv3.1: 7.7 [CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2021-27239

CWE-ID: CWE-121 - Stack-based buffer overflow

Exploit availability: No

Description

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

The vulnerability exists due to a boundary error within the upnpd service. A remote unauthenticated attacker on the local network can use a specially crafted MX header field in an SSDP message, trigger 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

D6220: before 1.0.0.68

XR300: before 1.0.3.56

WNR3500Lv2: before 1.2.0.66

WNDR3400v3: before 1.0.1.38

RS400: before 1.5.0.68_hotfix

RBS850: before 3.2.17.12

RBS750: before 3.2.17.12

RBS40V: before 2.6.2.4

RBR850: before 3.2.17.12

RBR750: before 3.2.17.12

RAX80: before 1.0.3.102

RAX75: before 1.0.3.102

RAX200: before 1.0.2.88

R8500: before 1.0.2.144

R8300: before 1.0.2.144

R8000P: before 1.4.1.68

R8000: before 1.0.4.68

R7960P: before 1.4.1.68

R7900P: before 1.4.1.68

R7900: before 1.0.4.38

R7850: before 1.0.5.68

R7100LG: before 1.0.0.64

R7000P: before 1.3.2.132

R7000: before 1.0.11.116

R6900P: before 1.3.2.132

R6700v3: before 1.0.4.102

R6400v2: before 1.0.4.102

R6400: before 1.0.1.68

R6300v2: before 1.0.4.50

R6250: before 1.0.4.48

EX7500: before 1.0.0.72

EX7000: before 1.0.1.94

DC112A: before 1.0.0.54

D8500: before 1.0.3.60

D6400: before 1.0.0.102

D7000v2: before 1.0.0.66

External links

http://www.zerodayinitiative.com/advisories/ZDI-21-206/
http://kb.netgear.com/000062820/Security-Advisory-for-Stack-based-Buffer-Overflow-Remote-Code-Execu...

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the local network (LAN).

Is there known malware, which exploits this vulnerability?

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