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CVE-2021-27256

Published: Mar 5, 2021Updated: Nov 21, 2024 Sources: CVE List NVDCWE-78
NVD MITRE
8.8CVSSHIGH
EPSS Score
0.9%
Top 46.0%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
Patch Available

Description

This vulnerability allows network-adjacent attackers to execute arbitrary code on affected installations of NETGEAR R7800 firmware version 1.0.2.76. Although authentication is required to exploit this vulnerability, the existing authentication mechanism can be bypassed. The specific flaw exists within the handling of the rc_service parameter provided to apply_save.cgi. The issue results from the lack of proper validation of a user-supplied string before using it to execute a system call. An attacker can leverage this vulnerability to execute code in the context of root. Was ZDI-CAN-12355.

CVSS Vector Breakdown

AV:AAC:LPR:NUI:NS:UC:HI:HA:H
Exploitability
AV:AAttack Vector
Adjacent
AC:LAttack Complexity
Low
PR:NPrivileges Required
None
UI:NUser Interaction
None
Scope
S:UScope
Unchanged
Impact
C:HConfidentiality
High
I:HIntegrity
High
A:HAvailability
High
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Weaknesses

CWE-78

Affected Products

R7800NETGEARNetworking Infrastructure
br200 firmwarenetgearNetworking Infrastructure
br500 firmwarenetgearNetworking Infrastructure
d7800 firmwarenetgearNetworking Infrastructure
ex6100v2 firmwarenetgearNetworking Infrastructure
netgearcommercialUSNetworking Infrastructureaka net gear
and 39 more affected products View all →

Attack Graph

Products CVE Techniques Tactics

Click technique nodes to view MITRE ATT&CK details. Scroll to zoom, drag to pan.

Exploitability

Official Patch Available

MITRE ATT&CK

1 technique
Execution
View detailed technique mapping

References

https://kb.netgear.com/000062883/Security-Advisory-for-Multiple-Vulnerabilities-on-Some-Routers-Satellites-and-Extenders
kb.netgear.com
https://www.zerodayinitiative.com/advisories/ZDI-21-262/
zerodayinitiative.com

Timeline

Published
Mar 5, 2021
Last Updated
Nov 21, 2024

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