CVE-2024-8948MicroPython objint.c mpz_as_bytes heap-based overflow
- 6.9MediumCVSS base score
- 0.98%Exploitation in 30 daysEPSS · top 37% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- YesPublic exploitsa reference or SSVC says so
Description
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.
Public exploit
An exploit or proof of concept is public: anyone can try it against an unpatched system. A reference of the record is tagged as an exploit. CISA's SSVC rates its exploitation: a proof of concept is public.
Show the exploits1
References tagged exploit1 reference
- https://github.com/micropython/micropython/issues/13041 (opens in a new tab)exploitissue-tracking
Timeline
ID reserved
By VulDB
Published
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| VulDBCNA (assigner) | 4.0 | Medium6.9 | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N |
| VulDBCNA (assigner) | 3.1 | High7.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L |
| VulDBCNA (assigner) | 3.0 | High7.3 | CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L |
| VulDBCNA (assigner) | 2.0 | High7.5 | AV:N/AC:L/Au:N/C:P/I:P/A:P |
| NVDNVD · Analyzed | 4.0 | Medium6.9 | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X |
- EPSS (exploitation in 30 days)
- 0.98% · top 37% of all CVEs (12 Nov 2026)
- CISA SSVC
- Exploitation: poc · Automatable: no · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 6.9.
Affected products
MicroPython
- affected 1.23.0
Affected packages
From reviewed advisories of the GitHub Advisory Database.
- PyPImicropython-copyGHSA-vh3x-525m-jp4r (opens in a new tab)
- PyPImicropython-ioGHSA-vh3x-525m-jp4r (opens in a new tab)
- PyPImicropython-osGHSA-vh3x-525m-jp4r (opens in a new tab)
References
References5
- VDB-277766 | MicroPython objint.c mpz_as_bytes heap-based overflow (opens in a new tab)vdb-entrytechnical-description
- VDB-277766 | CTI Indicators (IOB, IOC, IOA) (opens in a new tab)signaturepermissions-required
- Submit #409317 | micropython v1.23.0 Buffer Overflow (opens in a new tab)third-party-advisory
- https://github.com/micropython/micropython/issues/13041 (opens in a new tab)exploitissue-tracking
- https://github.com/micropython/micropython/commit/908ab1ceca15ee6fd0ef82ca4cba770a3ec41894 (opens in a new tab)patch
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2024-0101 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisory GHSA-vh3x-525m-jp4r (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2024-8948)Record last updated .