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CVE-2021-34947

Published: May 7, 2024Updated: Aug 14, 2025 Sources: CVE List NVD BDUCWE-787
NVD MITRE
8.8CVSSHIGH
EPSS Score
0.5%
Top 58.5%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
Patch Available

Description

NETGEAR R7800 net-cgi Out-Of-Bounds Write Remote Code Execution Vulnerability. This vulnerability allows network-adjacent attackers to execute arbitrary code on affected installations of NETGEAR R7800 routers. Authentication is not required to exploit this vulnerability. The specific flaw exists within the parsing of the soap_block_table file. The issue results from the lack of proper validation of user-supplied data, which can result in a write past the end of an allocated data structure. An attacker can leverage this vulnerability to execute code in the context of root. . Was ZDI-CAN-13055.

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
Open in CVSS calculator →

Weaknesses

CWE-787

Affected Products

d7800 firmwarenetgearNetworking Infrastructure
ex2700 firmwarenetgearNetworking Infrastructure
ex6100 firmwarenetgearNetworking Infrastructure
ex6150 firmwarenetgearNetworking Infrastructure
ex6200 firmwarenetgearNetworking Infrastructure
netgearcommercialUSNetworking Infrastructureaka net gear
and 46 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

2 techniques
Initial Access
Privilege Escalation
View detailed technique mapping

References

https://kb.netgear.com/000064044/Security-Advisory-for-Pre-Authentication-Buffer-Overflow-on-Some-Routers-PSV-2021-0129
kb.netgear.com
https://www.zerodayinitiative.com/advisories/ZDI-21-1116/
zerodayinitiative.com
https://www.zerodayinitiative.com/advisories/ZDI-21-1116/
zerodayinitiative.com
and 3 more references View all →

Timeline

Published
May 7, 2024
Last Updated
Aug 14, 2025

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