Vulnerability · Published Sep 17, 2024 · Assigned by VulDB
CVE-2024-8946MicroPython VFS Unmount vfs.c mp_vfs_umount heap-based overflow
High 7.3
In plain English
A high-severity heap buffer overflow in MicroPython. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 1.0% (higher than 63% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official 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.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:13 | micropython | 1.24.0+ds-1 | DEBIAN-CVE-2024-8946 |
| Debian:14 | micropython | 1.24.0+ds-1 | DEBIAN-CVE-2024-8946 |
| PyPI | micropython-copy | no fix listed | GHSA-74qm-4v7r-jw2f |
| PyPI | micropython-copy | no fix listed | PYSEC-2024-91 |
| PyPI | micropython-io | no fix listed | GHSA-74qm-4v7r-jw2f |
| PyPI | micropython-io | no fix listed | PYSEC-2024-93 |
| PyPI | micropython-os-path | no fix listed | PYSEC-2024-95 |
| PyPI | micropython-os-path | no fix listed | GHSA-74qm-4v7r-jw2f |
| PyPI | micropython-string | no fix listed | PYSEC-2024-96 |
| PyPI | micropython-string | no fix listed | GHSA-74qm-4v7r-jw2f |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| n/a | MicroPython | 1.23.0 |
Weakness: CWE-122 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L
References
- VDB-277764 | MicroPython VFS Unmount vfs.c mp_vfs_umount heap-based overflow vdb-entry, technical-description
- VDB-277764 | CTI Indicators (IOB, IOC, IOA) signature, permissions-required
- Submit #409312 | micropython v1.23.0 Heap-based Buffer Overflow third-party-advisory
- https://github.com/micropython/micropython/issues/13006 exploit, issue-tracking
- https://github.com/micropython/micropython/issues/13006#issuecomment-1820309455 issue-tracking
- https://github.com/micropython/micropython/commit/29943546343c92334e8518695a11fc0e2ceea68b patch