A AegiFlow
HIGHCVSS 8.1KNOWN EXPLOITED

CVE-2021-27137

CVE-2021-27137 updated by NVD

Published
2026-07-21
Modified
2026-07-31
Sources
cisa-kev, nvd

Summary

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).

References

Includes data from the CISA Known Exploited Vulnerabilities catalog.

Includes data from the National Vulnerability Database (NIST). NVD data is in the public domain; this page is not endorsed by NIST.

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