Vulnerability Description
lwIP TCP/IP Stack MQTT is vulnerable to an out-of-bounds write, which may allow an attacker to gain full code execution on the device.
CVSS Score
9.8
CRITICAL
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Related Weaknesses (CWE)
References
- https://github.com/cisagov/CSAF/blob/develop/csaf_files/OT/white/2026/icsa-26-26
- https://savannah.nongnu.org/projects/lwip
- https://www.cisa.gov/news-events/ics-advisories/icsa-26-265-01
FAQ
What is CVE-2026-87121?
CVE-2026-87121 is a vulnerability with a CVSS score of 9.8 (CRITICAL). lwIP TCP/IP Stack MQTT is vulnerable to an out-of-bounds write, which may allow an attacker to gain full code execution on the device.
How severe is CVE-2026-87121?
CVE-2026-87121 has been rated CRITICAL with a CVSS base score of 9.8/10. This is considered a critical vulnerability requiring immediate attention.
Is there a patch for CVE-2026-87121?
Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.