CVE-2026-56786: Rtklib

Critical severity, CVSS 9.8. EPSS: 0.7% chance of exploitation in the next 30 days.

RTKLIB through 2.4.3 contains an out-of-bounds write vulnerability in decode_type1033 function that fails to clamp length counters to destination buffer size, allowing up to 191-byte overflow into fixed 64-byte descriptor fields. An attacker controlling an NTRIP or serial RTCM3 correction stream can craft a valid CRC-bearing type-1033 message to corrupt adjacent rtcm_t object members, potentially achieving arbitrary code execution or denial of service.

Affected products

• Rtklib Rtklib: up to and including 2.4.3

Published 2026-06-25. Last modified 2026-07-14.