CVE-2026-11404

Cesanta Mongoose before 7.22 contains an out-of-bounds read in the built-in TLS server function mg_tls_server_recv_hello(), which uses an attacker-controlled session_id_len byte from a TLS ClientHello as a buffer index without validating it against the length of received data. A remote, unauthenticated attacker can send a single crafted ClientHello with an oversized session id length to read past the receive buffer, crashing any HTTPS, MQTTS, or WSS service built on MG_TLS_BUILTIN.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/cesanta/mongoose
https://github.com/cesanta/mongoose/releases/tag/7.22

Configurations

No configuration.

History

No history.

Information

Published : 2026-07-09 16:16

Updated : 2026-08-29 14:16

NVD link : CVE-2026-11404

Mitre link : CVE-2026-11404

CVE.ORG link : CVE-2026-11404

JSON object : View

Products Affected

No product.

CWE

CWE-125

Out-of-bounds Read

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