CVE-2021-47854
DD-WRT 45723 - UPNP Buffer Overflow
CVSS v3
9.8
CRITICAL
EPSS Score
1.1 %
exploit probability, as of 2026-09-25
CISA KEV
No
known exploited
Exploitation
poc
SSVC status
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.
Technical details
- Published
- 2026-01-21
- Last Modified
- 2026-04-14
Frequently asked questions
What is 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.
Is CVE-2021-47854 actively exploited?
A proof-of-concept exploit exists for CVE-2021-47854, but active exploitation has not been confirmed at this time.
What is the CVSS score for CVE-2021-47854?
CVE-2021-47854 has a CVSS v3 base score of 9.8 (CRITICAL severity).
Is CVE-2021-47854 affecting your environment?
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