OpenWrt’s Attended SysUpgrade (ASU) Vulnerability Exposes Routers to Malicious Firmware Attacks

Category	Details
Threat Actors	Not applicable (vulnerability exploitation by any malicious actors possible).
Campaign Overview	Exploitation of vulnerabilities in OpenWrt’s Attended SysUpgrade (ASU) server, enabling attackers to compromise firmware integrity by injecting malicious commands and exploiting hash collisions.
Target Regions (Or Victims)	OpenWrt users worldwide, including individuals and organizations relying on custom firmware for routers and network devices.
Methodology	– Command injection during firmware build process. – Exploiting SHA-256 hash collision due to truncated hashes. – Leveraging malicious package names to execute arbitrary commands in the build environment.
Product Targeted	OpenWrt operating system, specifically the Attended SysUpgrade (ASU) server.
Malware Reference	Malicious firmware images created during exploitation (no specific malware named).
Tools Used	NVIDIA RTX 4090 GPU, Hashcat (for brute-forcing hash collisions).
Vulnerabilities Exploited	– Command injection flaw in ImageBuilder service. – Truncated SHA-256 hashes causing hash collisions (CVE-2024-54143, CVSS 9.3).
TTPs	– Exploiting insufficient input sanitization. – Using shortened hashes to replace legitimate firmware. – Creating firmware that appears signed and legitimate to avoid detection.
Attribution	General exploitation possible; no specific threat actor attributed.
Recommendations	– Update OpenWrt devices with the latest patches immediately. – Avoid reliance on shortened hashes. – Implement strict input sanitization for critical processes. – Monitor systems for signs of malicious firmware.
Source	SOCRadar

Read full article: https://socradar.io/openwrts-attended-sysupgrade-vulnerability/

Disclaimer: The above summary has been generated by an AI language model