CVE-2023-7158: MicroPython objslice.c slice_indices heap-based overflow

Severity: critical (CVSS 9.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.2% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2023-12-29 · updated 2026-06-17
Weakness: CWE-122

Description

A vulnerability was found in MicroPython up to 1.21.0. It has been classified as critical. Affected is the function slice_indices of the file objslice.c. 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. Upgrading to version 1.22.0 is able to address this issue. It is recommended to upgrade the affected component. The identifier of this vulnerability is VDB-249180.

Affected products

MicroPython: before 1.22.0 — fixed in 1.22.0

How to fix

Upgrade to a fixed version: MicroPython 1.22.0. Check the vendor advisory for mitigations.

References

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