high
8.8
CWE
306
Advisory Published
Updated
Advisory Published

CVE-2021-27255: (Pwn2Own) NETGEAR R7800 funjsq_httpd Missing Authentication for Critical Function Remote Code Execution Vulnerability

First published: Fri Mar 05 2021(Updated: )

This vulnerability allows remote attackers to execute arbitrary code on affected installations of NETGEAR R7800 firmware version 1.0.2.76. Authentication is not required to exploit this vulnerability. The specific flaw exists within the refresh_status.aspx endpoint. The issue results from a lack of authentication required to start a service on the server. An attacker can leverage this vulnerability to execute code in the context of root. Was ZDI-CAN-12360.

Credit: zdi-disclosures@trendmicro.com

Affected SoftwareAffected VersionHow to fix
NETGEAR R7800
NETGEAR br200<5.10.0.5
NETGEAR BR200 Firmware
NETGEAR br500 firmware<5.10.0.5
NETGEAR br500 firmware
NETGEAR D7800<1.0.1.60
NETGEAR D7800 Firmware
NETGEAR EX6100v2 firmware<1.0.1.98
NETGEAR EX6100v2 firmware
NETGEAR EX6150v2 firmware<1.0.1.98
NETGEAR EX6150v2 firmware
NETGEAR EX6250<1.0.0.134
NETGEAR EX6250
NETGEAR EX6400 firmware<1.0.2.158
NETGEAR EX6400v2
NETGEAR EX6400v2 firmware<1.0.0.134
NETGEAR EX6400v2 firmware
NETGEAR EX6410<1.0.0.134
NETGEAR EX6410
NETGEAR EX6420<1.0.0.134
NETGEAR EX6420
NETGEAR EX7300<1.0.2.158
NETGEAR EX7300v2
NETGEAR EX7300v2 firmware<1.0.0.134
NETGEAR EX7300v2 firmware
NETGEAR EX7320<1.0.0.134
NETGEAR EX7320
NETGEAR EX7700<1.0.0.216
NETGEAR EX7700
NETGEAR EX8000<1.0.1.232
NETGEAR EX8000
NETGEAR LBR20 firmware<2.6.3.50
NETGEAR LBR20 firmware
NETGEAR R7800 firmware<1.0.2.80
NETGEAR R7800
NETGEAR R8900 firmware<1.0.5.28
NETGEAR R8900
NETGEAR R9000 firmware<1.0.5.28
NETGEAR R9000 firmware
NETGEAR RBK12 firmware<2.7.2.104
NETGEAR RBK12 firmware
NETGEAR rbk13 firmware<2.7.2.104
NETGEAR rbk13 firmware
NETGEAR rbk14 firmware<2.7.2.104
NETGEAR rbk14 firmware
NETGEAR RBK15 Firmware<2.7.2.104
NETGEAR RBK15 Firmware
NETGEAR RBK20 Router Firmware<2.6.2.104
NETGEAR RBK20 firmware
NETGEAR RBK23 Satellite Firmware<2.7.2.104
NETGEAR Orbi RBK23
NETGEAR RBK40<2.6.2.104
NETGEAR RBK40 firmware
NETGEAR RBK43<2.6.2.104
NETGEAR RBK43 Router Firmware
NETGEAR RBK43S Router Firmware<2.6.2.104
NETGEAR RBK43S Firmware
NETGEAR RBK44 Satellite Firmware<2.6.2.104
NETGEAR RBK44 Satellite Firmware
NETGEAR RBK50 firmware<2.7.2.104
NETGEAR RBK50
NETGEAR RBK53 Firmware<2.7.2.104
NETGEAR Orbi RBK53
NETGEAR RBR10 firmware<2.6.2.104
NETGEAR RBR10 firmware
NETGEAR RBR20<2.6.2.104
NETGEAR RBR20
NETGEAR CBR40 firmware<2.6.2.104
NETGEAR RBR40 firmware
NETGEAR RBR50 firmware<2.7.2.104
NETGEAR RBR50 firmware
NETGEAR RBS10<2.6.2.104
NETGEAR RBS10 firmware
NETGEAR RBS20 firmware<2.6.2.104
NETGEAR RBS20 firmware
NETGEAR RBS40 firmware<2.6.2.104
NETGEAR RBS40 firmware
NETGEAR RBS50 firmware<2.7.2.104
NETGEAR RBS50
NETGEAR RBS50Y firmware<2.6.2.104
NETGEAR RBS50Y firmware
NETGEAR XR450 firmware<2.3.2.114
NETGEAR XR450 firmware
NETGEAR XR500 firmware<2.3.2.114
NETGEAR XR500 firmware
NETGEAR XR700<1.0.1.38
NETGEAR XR700 firmware

Remedy

https://kb.netgear.com/000062883/Security-Advisory-for-Multiple-Vulnerabilities-on-Some-Routers-Satellites-and-Extenders

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Reference Links

Frequently Asked Questions

  • What is the severity of CVE-2021-27255?

    CVE-2021-27255 has a critical severity rating due to the possibility of remote code execution without authentication.

  • How do I fix CVE-2021-27255?

    To fix CVE-2021-27255, upgrade your NETGEAR R7800 firmware to version 1.0.2.80 or later.

  • Which NETGEAR devices are affected by CVE-2021-27255?

    CVE-2021-27255 primarily affects NETGEAR R7800 firmware version 1.0.2.76 and earlier.

  • Can CVE-2021-27255 be exploited without user authentication?

    Yes, CVE-2021-27255 can be exploited by attackers remotely without requiring any user authentication.

  • Is there any workaround for CVE-2021-27255 if I cannot update immediately?

    Currently, there are no reliable workarounds for CVE-2021-27255 other than updating the firmware to a secure version.

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