CVE-2021-27137 - CVE House
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Status published High CVE-2021-27137

An issue was discovered in router/upnp/src/ssdp.c in DD-WRT before 45724....

Vulnerability Description

An issue was discovered in router/upnp/src/ssdp.c in DD-WRT before 45724. An unsafe strcpy in the UPnP handling functionality allows an unauthenticated remote attacker to send a request that would overflow an internal fixed buffer. Exploitation requires the DD-WRT user to enable UPnP (which is off by default, and only listens on internal interfaces by default). This occurs in ssdp_msearch (reachable by an M-SEARCH request).

Impact Analysis

Refer to official advisory for detailed impact metrics.

Remediation

Ensure systems are updated to the latest vendor-supplied patch levels.

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Credits & Attribution

No credits recorded in the NVD database.

Affected Vendor

Affected Software

DD-WRT
Vulnerable Versions:
0

Timeline

Official Publish: July 16th, 2026
Last Modified: July 16th, 2026
Added to House: July 21st, 2026

CVSS Vectors

V3: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

Weaknesses (CWE)