CVE-2026-87121

CVSS 9.8 (critical) · published 2026-09-22

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.

Weakness: CWE-787

Source: NVD CVE-2026-87121

References

• https://github.com/cisagov/CSAF/blob/develop/csaf_files/OT/white/2026/icsa-26-265-01.json
• https://savannah.nongnu.org/projects/lwip
• https://www.cisa.gov/news-events/ics-advisories/icsa-26-265-01

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