CVE-2021-27137
DD-WRT contains a stack-based buffer overflow vulnerability that could allow an unauthenticated attacker to overflow an internal buffer used by UPnP and trigger a code execution vulnerability.
Ver en NVDAnálisis
DD-WRT firmware before version 45724 is vulnerable to a stack-based buffer overflow in its UPnP handling. An attacker on the local network could potentially achieve remote code execution, though the feature is disabled by default and restricted to internal interfaces.
Roles relevantes
Severidad
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:HCWE-121CISA KEV
Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.
EPSS
Descripción técnica
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).
Referencias
- 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