CVE-2021-27137

EUVD-2021-34854
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).
ProviderTypeBase ScoreAtk. VectorAtk. ComplexityPriv. RequiredVector
NISTPrimary
8.1 HIGH
NETWORK
HIGH
NONE
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
Base Score
CVSS 3.x
EPSS Score
Percentile: 89.78%
Affected Products (NVD)
VendorProductVersion
dd-wrtdd-wrt
𝑥
< 45724
𝑥
= Vulnerable software versions
Common Weakness Enumeration
References
https://securityaffairs.com/193290/uncategorized/iot-botnet-c0xmo-adds-competitor-killing-capability.html
https://ssd-disclosure.com/ssd-advisory-dd-wrt-upnp-buffer-overflow/
https://svn.dd-wrt.com/changeset/45724
https://www.bleepingcomputer.com/news/security/c0xmo-botnet-spreads-via-dd-wrt-router-flaw-kills-rival-malware/
https://www.fortinet.com/blog/threat-research/inside-cross-platform-propagation-of-new-gafgyt-variant-c0xmo
https://ssd-disclosure.com/ssd-advisory-dd-wrt-upnp-buffer-overflow/
https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-27137