Horizon Alert
Summary of the vulnerability and why it matters
An issue in DD-WRT's UPnP handling could allow an attacker to overflow a buffer. This vulnerability, if exploited, could lead to code execution. The main concern is confirming relevance and exposure, as UPnP is off by default and typically listens only on internal interfaces.
- Unauthenticated attackers can overflow a buffer.
- This flaw can allow rival malware to spread.
- Confirm relevance and exposure of UPnP usage.
Attack Path
How an attacker could exploit the issue
An attacker could exploit this vulnerability by sending a specially crafted request to a router running DD-WRT. If the router has Universal Plug and Play (UPnP) enabled, which is not the default, the attacker could trigger a buffer overflow. This overflow could lead to the execution of arbitrary code, allowing the attacker to compromise the device.
- Requires UPnP to be enabled.
- Triggered by an M-SEARCH request.
- Can lead to remote code execution.
Live Threat
Current exploitation, exposure, and threat context
An unsafe buffer copy in the UPnP functionality could allow an unauthenticated remote attacker to cause a buffer overflow when the feature is enabled and accessible. This could affect the integrity and availability of the router's services.
- Router system data at risk.
- Unauthenticated remote request can trigger overflow.
- Service disruption and potential code execution.
Operational Fix
Recommended remediation, mitigation, and detection steps
This vulnerability impacts DD-WRT router firmware with UPnP enabled, potentially affecting device owners and network administrators. The initial practical step is to determine if UPnP is active and if the affected interfaces are exposed externally. If so, identify the specific DD-WRT instances, assess their business criticality, and assign ownership for remediation.
- Identify impacted DD-WRT devices.
- Verify UPnP is enabled and exposed.
- Plan remediation based on risk.
