UBR Device Authentication and File Access

Unauthorized firmware upload via wwwupdate.cgi endpoint due to insufficient authorization. Remote attackers can upload and apply arbitrary firmware updates.

Unauthorized file upload via wwwupload.cgi endpoint. Same product as CVE-2025-41764 — second unauthorized upload vector.

A low-privileged remote attacker can abuse the backup restore functionality of UBR (ubr-restore) which runs with elevated privileges and does not validate the contents of the backup archive to create or overwrite arbitrary files anywhere on the system. [CVSS 8.8 HIGH]

A low-privileged remote attacker can exploit an arbitrary file write vulnerability in the wwupload.cgi endpoint. Due to path traversal this can lead to overwriting arbitrary files on the device and achieving a full system compromise. [CVSS 8.8 HIGH]

A low-privileged remote attacker can trigger a stack-based buffer overflow via a crafted HTTP POST request using the ubr-network method resulting in full device compromise. [CVSS 8.8 HIGH]

A low-privileged remote attacker can exploit the ubr-editfile method in wwwubr.cgi, an undocumented and unused API endpoint to write arbitrary files on the system. [CVSS 8.1 HIGH]

A low‑privileged local attacker who gains access to the UBR service account (e.g., via SSH) can escalate privileges to obtain full system access. This is due to the service account being permitted to execute certain binaries (e.g., tcpdump and ip) with sudo. [CVSS 7.8 HIGH]

An unauthenticated remote attacker can obtain valid session tokens because they are exposed in plaintext within the URL parameters of the wwwupdate.cgi endpoint in UBR. [CVSS 7.5 HIGH]

Universal Bacnet Router Firmware is affected by improper verification of cryptographic signature (CVSS 7.2).

A low-privileged remote attacker can exploit the ubr-editfile method in wwwubr.cgi, an undocumented and unused API endpoint to read arbitrary files on the system. [CVSS 6.5 MEDIUM]

A low‑privileged remote attacker can directly interact with the wwwdnload.cgi endpoint to download any resource available to administrators, including system backups and certificate request files. [CVSS 6.5 MEDIUM]

A low-privileged remote attacker can exploit the ubr-logread method in wwwubr.cgi to read arbitrary files on the system. [CVSS 6.5 MEDIUM]

An unauthenticated attacker can abuse the weak hash of the backup generated by the wwwdnload.cgi endpoint to gain unauthorized access to sensitive data, including password hashes and certificates. [CVSS 6.2 MEDIUM]

An administrator may attempt to block all networks by specifying "\*" or "all" as the network identifier. However, these values are not supported and do not trigger any validation error. [CVSS 4.9 MEDIUM]

An administrator may attempt to block all traffic by configuring a pass filter with an empty table. However, in UBR, an empty list does not enforce any restrictions and allows all network traffic to pass unfiltered. [CVSS 4.9 MEDIUM]