CVE-2024-8946: micropython Heap Overflow

Description

A vulnerability was found in MicroPython 1.23.0. It has been classified as critical. Affected is the function mp_vfs_umount of the file extmod/vfs.c of the component VFS Unmount Handler. The manipulation leads to heap-based buffer overflow. It is possible to launch the attack remotely. The exploit has been disclosed to the public and may be used. The name of the patch is 29943546343c92334e8518695a11fc0e2ceea68b. It is recommended to apply a patch to fix this issue. In the VFS unmount process, the comparison between the mounted path string and the unmount requested string is based solely on the length of the unmount string, which can lead to a heap buffer overflow read.

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CVSS v3.1 Score

7.3

HIGH

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

Weakness Type (CWE)

CWE-122 CWE-122

CWE-787 Out-of-bounds Write

Affected Products

Vendor	Product	Versions
micropython	micropython	All

References

Advisories & Patches

https://github.com/micropython/micropython/commit/29943546343c92334e8518695a11fc0e2ceea68b

Exploits

https://github.com/micropython/micropython/issues/13006 https://github.com/micropython/micropython/issues/13006#issuecomment-1820309455

Other References

https://vuldb.com/?ctiid.277764 https://vuldb.com/?id.277764 https://vuldb.com/?submit.409312

Frequently Asked Questions

What is CVE-2024-8946? +

A vulnerability was found in MicroPython 1.23.0. It has been classified as critical. Affected is the function mp_vfs_umount of the file extmod/vfs.c of the component VFS Unmount Handler. The manipulation leads to heap-based buffer overflow. It is possible to launch the attack remotely. The exploit has been disclosed to the public and may be used. The name of the patch is 29943546343c92334e8518695a11fc0e2ceea68b. It is recommended to apply a patch to fix this issue. In the VFS unmount process, the comparison between the mounted path string and the unmount requested string is based solely on the length of the unmount string, which can lead to a heap buffer overflow read. It has a CVSS v3.1 base score of 7.3 (HIGH).

How severe is CVE-2024-8946? +

CVE-2024-8946 has a CVSS v3.1 score of 7.3 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching.

What products are affected by CVE-2024-8946? +

CVE-2024-8946 affects products from micropython, specifically: micropython. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2024-8946? +

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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