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).
History

Tue, 21 Jul 2026 16:30:00 +0000

Type Values Removed Values Added
References
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'poc', 'Technical Impact': 'total'}, 'version': '2.0.3'}

ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'active', 'Technical Impact': 'total'}, 'version': '2.0.3'}


Tue, 21 Jul 2026 15:00:00 +0000

Type Values Removed Values Added
Metrics kev

{'dateAdded': '2026-07-21T00:00:00+00:00', 'dueDate': '2026-07-24T00:00:00+00:00'}


Thu, 16 Jul 2026 19:30:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'poc', 'Technical Impact': 'total'}, 'version': '2.0.3'}


Thu, 16 Jul 2026 18:00:00 +0000

Type Values Removed Values Added
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).
First Time appeared Dd-wrt
Dd-wrt dd-wrt
Weaknesses CWE-121
CPEs cpe:2.3:a:dd-wrt:dd-wrt:*:*:*:*:*:*:*:*
Vendors & Products Dd-wrt
Dd-wrt dd-wrt
References
Metrics cvssV3_1

{'score': 8.1, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H'}


cve-icon MITRE

Status: PUBLISHED

Assigner: mitre

Published: 2026-07-16T00:00:00.000Z

Updated: 2026-07-22T03:55:45.793Z

Reserved: 2021-02-10T00:00:00.000Z

Link: CVE-2021-27137

cve-icon Vulnrichment

Updated: 2026-07-16T18:24:33.515Z

cve-icon NVD

No data.

cve-icon Redhat

No data.