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TI-2024-08308 Aliases CVE-2024-8948GHSA-vh3x-525m-jp4r

MicroPython objint.c mpz_as_bytes heap-based overflow

Priority MEDIUM 64CWE-122Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Attack requirements
None
Impact type
—
Confidentiality · integrity · availability
Low · Low · Low
Fix status
No fix listed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA and GitHub.

Summary

A vulnerability was found in MicroPython 1.23.0. It has been rated as critical. Affected by this issue is the function mpz_as_bytes of the file py/objint.c. The manipulation leads to heap-based buffer overflow. The attack may be launched remotely. The exploit has been disclosed to the public and may be used. The patch is identified as 908ab1ceca15ee6fd0ef82ca4cba770a3ec41894. It is recommended to apply a patch to fix this issue. In micropython objint component, converting zero from int to bytes leads to heap buffer-overflow-write at mpz_as_bytes.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00985 62nd percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by the CNA and NVD
Fix No fix listed No fixed version in the sources yet

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
—MicroPython1.23.0—No fix listedCNA
—micropython-copy (PyPI)up to 3.3.3.post3—No fix listedGHSA-vh3x-525m-jp4r
—micropython-io (PyPI)up to 0.1—No fix listedGHSA-vh3x-525m-jp4r
—micropython-os (PyPI)up to 0.8—No fix listedGHSA-vh3x-525m-jp4r
  • MicroPython Vendor— Affected 1.23.0 Fixed in — No fix listed CNA
  • micropython-copy (PyPI) Vendor— Affected up to 3.3.3.post3 Fixed in — No fix listed GHSA-vh3x-525m-jp4r
  • micropython-io (PyPI) Vendor— Affected up to 0.1 Fixed in — No fix listed GHSA-vh3x-525m-jp4r
  • micropython-os (PyPI) Vendor— Affected up to 0.8 Fixed in — No fix listed GHSA-vh3x-525m-jp4r

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:micropython:micropython:1.23.0:*:*:*:*:*:*:*1.23.0VulnerableMicropython
  • cpe:2.3:a:micropython:micropython:1.23.0:*:*:*:*:*:*:* Versions 1.23.0 Vulnerable ·Micropython

Remediation

No fixed version listed by the sources yet.

Vendor assessments

Red Hat

Red Hat's page for this CVE →

Not affected: 1 product
  • Red Hat

Timeline

  1. 2026-10-02 Threatist record created from CVE-2024-8948
  2. 2026-10-03 Alias added: GHSA-vh3x-525m-jp4r

References

Exploit 1

Patch 1

Advisory 1

Other 3

  • TI-2024-08306 MicroPython VFS Unmount vfs.c mp_vfs_umount heap-based overflow CVSS 4.0MEDIUM 6.9
  • TI-2024-08307 MicroPython objarray.c use after free CVSS 4.0MEDIUM 6.3
  • TI-2026-01655 micropython runtime.c mp_import_all memory corruption CVSS 4.0MEDIUM 4.8
  • TI-2023-06546 MicroPython objslice.c slice_indices heap-based overflow CVSS 3.1CRITICAL 9.8
  • TI-2023-06540 MicroPython modselect.c poll_set_add_fd use after free CVSS 3.1CRITICAL 9.8

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences