CVE-2026-87121

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 v3 9.8 CRITICAL

9.8^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
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

Configurations

No configuration.

History

22 Sep 2026, 20:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-09-22 20:17

Updated : 2026-09-23 19:42

NVD link : CVE-2026-87121

Mitre link : CVE-2026-87121

CVE.ORG link : CVE-2026-87121

JSON object : View

Products Affected

No product.

CWE

CWE-787

Out-of-bounds Write

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