How severe is CVE-2024-8946?

CVE-2024-8946 has a CVSS 3.x base score of 7.3, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability low.

Is CVE-2024-8946 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (59th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2024-8946?

CVE-2024-8946 affects Micropython. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2024-8946?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

Does CVE-2024-8946 have an EU (EUVD) identifier?

Yes. CVE-2024-8946 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2024-0102.

When was CVE-2024-8946 published?

CVE-2024-8946 was published on 2024-09-17 and last updated on 2026-06-17.

CVE-2024-8946

CVE-2024-8946 is a high-severity vulnerability in Micropython with a CVSS 3.x base score of 7.3. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-787.

Key facts

Severity: High (CVSS 3.x base score 7.3)
CVSS v2: 7.5
CVSS v4: 6.9
EPSS exploit prediction: 1% (59th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2024-0102
Weakness: CWE-787
Affected product: Micropython
Published: 2024-09-17
Last modified: 2026-06-17

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.

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.
How severe is CVE-2024-8946?: CVE-2024-8946 has a CVSS 3.x base score of 7.3, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability low.
Is CVE-2024-8946 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (59th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2024-8946?: CVE-2024-8946 affects Micropython. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2024-8946?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
Does CVE-2024-8946 have an EU (EUVD) identifier?: Yes. CVE-2024-8946 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2024-0102.
When was CVE-2024-8946 published?: CVE-2024-8946 was published on 2024-09-17 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:micropython:micropython:1.23.0:*:*:*:*:*:*:*

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