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R8900 Firmware CVE-2021-27255

HIGH
Missing Authentication for Critical Function (CWE-306)
2021-03-05 zdi-disclosures@trendmicro.com
Authentication Bypass RCE Netgear R8900 Firmware R9000 Firmware Rbr20 Firmware Rbs20 Firmware Ex8000 Firmware D7800 Firmware R7800 Firmware Xr500 Firmware Xr700 Firmware Rbk20 Firmware Rbr40 Firmware Rbs40 Firmware Rbk40 Firmware Rbr50 Firmware Rbs50 Firmware Rbk50 Firmware Ex6400 Firmware Ex7300 Firmware Xr450 Firmware Rbs50Y Firmware Ex7700 Firmware Rbk12 Firmware Rbr10 Firmware Rbs10 Firmware Ex6100V2 Firmware Ex6150V2 Firmware Ex6250 Firmware Ex6400V2 Firmware Ex6410 Firmware Ex7300V2 Firmware Ex7320 Firmware Rbk13 Firmware Rbk14 Firmware Rbk15 Firmware Br200 Firmware Br500 Firmware Ex6420 Firmware Lbr20 Firmware Rbk23 Firmware Rbk43 Firmware Rbk43S Firmware Rbk44 Firmware Rbk53 Firmware
8.8
CVSS 3.1 · NVD
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Severity by source

NVD PRIMARY
8.8 HIGH
AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Primary rating from NVD · only source for this CVE.

CVSS VectorNVD

Attack Vector
Adjacent
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

Lifecycle Timeline

1
CVE Published
Mar 05, 2021 - 20:15 nvd
HIGH 8.8

DescriptionNVD

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.

AnalysisAI

This vulnerability allows remote attackers to execute arbitrary code on affected installations of NETGEAR R7800 firmware version 1.0.2.76. Rated high severity (CVSS 8.8), this vulnerability is no authentication required, low attack complexity. This Missing Authentication for Critical Function vulnerability could allow attackers to access critical functionality without authentication.

Technical ContextAI

This vulnerability is classified as Missing Authentication for Critical Function (CWE-306), which allows attackers to access critical functionality without authentication. 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. Affected products include: Netgear Br200 Firmware, Netgear Br500 Firmware, Netgear D7800 Firmware, Netgear Ex6100V2 Firmware, Netgear Ex6150V2 Firmware. Version information: version 1.0.2.76..

RemediationAI

A vendor patch is available. Apply the latest security update as soon as possible. Require authentication for all sensitive operations, implement defense in depth.

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CVE-2021-27255 vulnerability details – vuln.today
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