Submit #818237: Tomato by Shibby Tomato Firmware 1.28 Out-of-Bounds Read

An information disclosure vulnerability exists in usr/sbin/miniupnpd in Tomato by Shibby firmware. In the SUBSCRIBE callback handling path, the daemon stores an attacker-controlled callback URI and later constructs the initial NOTIFY request in a fixed 0x400-byte heap buffer. The code uses the return value of snprintf() as the transmit length without checking whether the formatted length exceeded the allocated buffer size. As a result, a sufficiently long callback path can cause send() to transmit bytes beyond the intended 0x400-byte buffer, disclosing unintended heap memory and adjacent message data to the subscribing client.

The current evidence supports LAN-side unauthenticated information disclosure. The callback host is constrained to the requester's own IPv4 address, so the supported impact is memory disclosure back to the subscriber-controlled listener, not arbitrary SSRF.

• Source: ⚠️ https://gitee.com/Fengyi-Wang/CVE/issues/IJD8SS
• User: Anonymous User
• Submission: 05/02/2026 18:41 (2 months ago)
• Moderation: 05/29/2026 10:33 (27 days later)
• Status: Accepted
• VulDB entry: 367154 [Shibby Tomato 1.28 SUBSCRIBE Call usr/sbin/miniupnpd send server-side request forgery]
• Points: 20