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CVE-2021-27239

Published: Mar 29, 2021Updated: Nov 21, 2024 Sources: CVE List NVDCWE-121
8.8HIGH
NVD MITRE
EPSS Score
0.7%
Top 48.6%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
Patch Available
Self-Check
Not 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.

No summary for this CVE yet.

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-121

Affected Products

NETGEAR
commercial·USaka net gear
Multiple Routers
Networking Infrastructure
d6220 firmware
Networking Infrastructure
d6400 firmware
Networking Infrastructure
d7000 firmware
Networking Infrastructure
d8500 firmware
Networking Infrastructure
dc112a firmware
Networking Infrastructure
ex7000 firmware
Networking Infrastructure
ex7500 firmware
Networking Infrastructure
and 28 more affected products View all →

Exploitability

Official Patch Available
Is your org exposed to CVE-2021-27239?We can run the check for you — a free external exposure review, no install. Check my exposure

Attack Graph

Products CVE Techniques Tactics

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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

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