CVE-2026-3613: Wavlink WL-NU516U1 login.cgi sub_401A0C stack-based overflow

Vulnerability summary

CVE-2026-3613 is a high (CVSS 8.6) vulnerability in wavlink wl-nu516u1_firmware. EPSS estimates a 1.17% chance of exploitation in the next 30 days, higher than 67.2% of scored vulnerabilities. 1 public exploit is recorded.

Timeline

1. 06-03-2026
   PublishedVulnerability first disclosed.
2. 09-03-2026
   Last modifiedVulnerability information updated.

Description

A vulnerability was identified in Wavlink WL-NU516U1 V240425. This vulnerability affects the function sub_401A0C of the file /cgi-bin/login.cgi. Such manipulation of the argument ipaddr leads to stack-based buffer overflow. It is possible to launch the attack remotely. The exploit is publicly available and might be used. The vendor was contacted early about this disclosure.

• CWE-119Improper Restriction of Operations within the Bounds of a Memory BufferThe product performs operations on a memory buffer, but it reads from or writes to a memory location outside the buffer's intended boundary. This may result in read or write operations on unexpected memory locations that could be linked to other variables, data structures, or internal program data.
• CWE-121Stack-based Buffer OverflowA stack-based buffer overflow condition is a condition where the buffer being overwritten is allocated on the stack (i.e., is a local variable or, rarely, a parameter to a function).