CVE-2026-87121 (GCVE-0-2026-87121)
Vulnerability from cvelistv5 – Published: 2026-09-22 19:48 – Updated: 2026-09-22 20:23
VLAI
EPSS
VEX
Title
Out-of-bounds write in lwIP TCP/IP Stack MQTT Client Application
Summary
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.
Severity
9.8 (Critical)
SSVC
Exploitation: none
Automatable: yes
Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-22 20:23 UTC
CWE
Assigner
References
Impacted products
1 product
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| lwIP | TCP/IP Stack MQTT |
Affected:
2.0.1 , ≤ 2.2.1
(custom)
|
guessed |
Date Public
2026-09-22 17:53
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