CVE-2021-47854

DD-WRT 45723 - UPNP Buffer Overflow

Published: Jan 21, 2026Updated: Jan 26, 2026 Sources: CVE List NVDCWE-120

9.8CRITICAL

Description

DD-WRT version 45723 contains a buffer overflow vulnerability in the UPNP network discovery service that allows remote attackers to potentially execute arbitrary code. Attackers can send crafted M-SEARCH packets with oversized UUID payloads to trigger buffer overflow conditions on the target device.

No summary for this CVE yet.

CVSS Vector Breakdown

Exploitability

AV:NAttack Vector

Network

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-120

Affected Products

embeDD GmbH

commercial

DD-WRTEmbedded

Networking Infrastructure / router-switch

Exploitability

1 exploit source identified

Exploit details including PoC links, Metasploit modules, and scanner templates are available after registration.

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Attack Graph

Products CVE Techniques Tactics

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MITRE ATT&CK

2 techniques

Initial Access

Privilege Escalation

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References

https://dd-wrt.com/

dd-wrt.com

https://download1.dd-wrt.com/dd-wrtv2/downloads/betas/2021/

download1.dd-wrt.com

https://ssd-disclosure.com/ssd-advisory-dd-wrt-upnp-buffer-overflow/

ssd-disclosure.com

and 2 more references View all →

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