CVE-2025-56353_CVE-2025-56353

7.5 / 10

HIGH

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Description

In tinyMQTT commit 6226ade15bd4f97be2d196352e64dd10937c1962 (2024-02-18), a memory leak occurs due to the broker's failure to validate or reject malformed UTF-8 strings in topic filters. An attacker can exploit this by sending repeated subscription requests with arbitrarily large or invalid filter payloads. Each request causes memory to be allocated for the malformed topic filter, but the broker does not free the associated memory, leading to unbounded heap growth and potential denial of service under sustained attack.

Basic Information

ID CVE-2025-56353

Source mitre

Published Jan 20, 2026 at 00:00

Modified Jan 21, 2026 at 14:39

Affected Product

Vendor n/a

Product n/a

Version n/a

Affected Versions n/a n/a n/a

CWE Classification

CWE-401

References

github.com /JustDoIt0910/tinyMQTT/issues/19

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    "published": "2026-01-20T00:00:00.000Z",
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