CVE-2025-65503: async mqtt Use-After-Free

Description

Use after free in endpoint destructors in Redboltz async_mqtt 10.2.5 allows local users to cause a denial of service via triggering SSL initialization failure that results in incorrect destruction order between io_context and endpoint objects.

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CVSS v3.1 Score

5.5

MEDIUM

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

Weakness Type (CWE)

CWE-416 Use After Free

Affected Products

Vendor	Product	Versions
redboltz	async_mqtt	All

References

Advisories & Patches

https://github.com/redboltz/async_mqtt/issues/436 https://github.com/redboltz/async_mqtt/pull/437

Exploits

https://github.com/redboltz/async_mqtt/issues/436

Frequently Asked Questions

What is CVE-2025-65503? +

Use after free in endpoint destructors in Redboltz async_mqtt 10.2.5 allows local users to cause a denial of service via triggering SSL initialization failure that results in incorrect destruction order between io_context and endpoint objects. It has a CVSS v3.1 base score of 5.5 (MEDIUM).

How severe is CVE-2025-65503? +

CVE-2025-65503 has a CVSS v3.1 score of 5.5 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance.

What products are affected by CVE-2025-65503? +

CVE-2025-65503 affects products from redboltz, specifically: async_mqtt. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2025-65503? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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