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National Vulnerability Database

National Vulnerability Database

NVD

National Vulnerability Database
  1. Vulnerabilities

CVE-2021-27137 Detail

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).


Metrics

 
NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.
CVSS 4.0 Severity and Vector Strings:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.

References to Advisories, Solutions, and Tools

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URL Source(s) Tag(s)
https://securityaffairs.com/193290/uncategorized/iot-botnet-c0xmo-adds-competitor-killing-capability.html MITRE
https://ssd-disclosure.com/ssd-advisory-dd-wrt-upnp-buffer-overflow/ CISA-ADP, MITRE
https://svn.dd-wrt.com/changeset/45724 MITRE
https://www.bleepingcomputer.com/news/security/c0xmo-botnet-spreads-via-dd-wrt-router-flaw-kills-rival-malware/ MITRE
https://www.fortinet.com/blog/threat-research/inside-cross-platform-propagation-of-new-gafgyt-variant-c0xmo MITRE

Weakness Enumeration

CWE-ID CWE Name Source
CWE-121 Stack-based Buffer Overflow MITRE  

Change History

2 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2021-27137
NVD Published Date:
07/16/2026
NVD Last Modified:
07/16/2026
Source:
MITRE