CVE-2021-47854

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.

CVSS v3 9.8 CRITICAL

9.8^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://dd-wrt.com/
https://download1.dd-wrt.com/dd-wrtv2/downloads/betas/2021/
https://ssd-disclosure.com/ssd-advisory-dd-wrt-upnp-buffer-overflow/
https://www.exploit-db.com/exploits/49730
https://www.vulncheck.com/advisories/dd-wrt-upnp-buffer-overflow

Configurations

No configuration.

History

21 Jan 2026, 18:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-01-21 18:16

Updated : 2026-01-26 15:04

NVD link : CVE-2021-47854

Mitre link : CVE-2021-47854

CVE.ORG link : CVE-2021-47854

JSON object : View

Products Affected

No product.

CWE

CWE-120

Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')

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