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CVE-2021-27239

Published: Mar 29, 2021Updated: Nov 21, 2024 Sources: CVE List NVDCWE-121
NVD MITRE
8.8CVSSHIGH
EPSS Score
0.7%
Top 50.1%
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 R6400 and R6700 firmware version 1.0.4.98 routers. Authentication is not required to exploit this vulnerability. The specific flaw exists within the upnpd service, which listens on UDP port 1900 by default. A crafted MX header field in an SSDP message can trigger an overflow of a fixed-length stack-based buffer. An attacker can leverage this vulnerability to execute code in the context of root. Was ZDI-CAN-11851.

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-121

Affected Products

Multiple RoutersNETGEARNetworking Infrastructure
d6220 firmwarenetgearNetworking Infrastructure
d6400 firmwarenetgearNetworking Infrastructure
d7000 firmwarenetgearNetworking Infrastructure
d8500 firmwarenetgearNetworking Infrastructure
netgearcommercialUSNetworking Infrastructureaka net gear
and 31 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
Privilege Escalation
View detailed technique mapping

References

https://www.zerodayinitiative.com/advisories/ZDI-21-206/
zerodayinitiative.com
https://kb.netgear.com/000062820/Security-Advisory-for-Stack-based-Buffer-Overflow-Remote-Code-Execution-Vulnerability-on-Some-Routers-PSV-2020-0432
kb.netgear.com

Timeline

Published
Mar 29, 2021
Last Updated
Nov 21, 2024

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