CVE-2024-36844: libmodbus Use-After-Free

Description

libmodbus v3.1.6 was discovered to contain a use-after-free via the ctx->backend pointer. This vulnerability allows attackers to cause a Denial of Service (DoS) via a crafted message sent to the unit-test-server.

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CVSS v3.1 Score

7.5

HIGH

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

Weakness Type (CWE)

CWE-416 Use After Free

Affected Products

Vendor	Product	Versions
libmodbus	libmodbus	All

References

Advisories & Patches

https://github.com/stephane/libmodbus/issues/749 https://github.com/stephane/libmodbus/issues/749

Exploits

https://github.com/stephane/libmodbus/issues/749 https://github.com/stephane/libmodbus/issues/749

Other References

https://lists.debian.org/debian-lts-announce/2025/03/msg00010.html

Frequently Asked Questions

What is CVE-2024-36844? +

libmodbus v3.1.6 was discovered to contain a use-after-free via the ctx->backend pointer. This vulnerability allows attackers to cause a Denial of Service (DoS) via a crafted message sent to the unit-test-server. It has a CVSS v3.1 base score of 7.5 (HIGH).

How severe is CVE-2024-36844? +

CVE-2024-36844 has a CVSS v3.1 score of 7.5 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching.

What products are affected by CVE-2024-36844? +

CVE-2024-36844 affects products from libmodbus, specifically: libmodbus. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2024-36844? +

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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