CVE-2025-67269: Gpsd Project Gpsd

High severity, CVSS 7.5. EPSS: 0.6% chance of exploitation in the next 30 days.

An integer underflow vulnerability exists in the `nextstate()` function in `gpsd/packet.c` of gpsd versions prior to commit `ffa1d6f40bca0b035fc7f5e563160ebb67199da7`. When parsing a NAVCOM packet, the payload length is calculated using `lexer->length = (size_t)c - 4` without checking if the input byte `c` is less than 4. This results in an unsigned integer underflow, setting `lexer->length` to a very large value (near `SIZE_MAX`). The parser then enters a loop attempting to consume this massive number of bytes, causing 100% CPU utilization and a Denial of Service (DoS) condition.

Affected products

• Gpsd Project Gpsd: before 3.27.1 (fixed in 3.27.1)

Published 2026-01-02. Last modified 2026-07-15.