# CVE-2021-33430: numpy: A Buffer Overflow vulnerability exists in NumPy 1.9.x in the PyArray_NewFromDescr_int function of ctors.c when specif...

CVE-2021-33430 is fixed in 2 products on 1 platform, first by python3-numpy 1:1.17.4-5ubuntu3.1, released December 17, 2021. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2021-33430
- Priority: Routine
- CVSS: 5.3 (medium)
- EPSS: 0.0153
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Dec 17, 2021

## Description

A Buffer Overflow vulnerability exists in NumPy 1.9.x in the PyArray_NewFromDescr_int function of ctors.c when specifying arrays of large dimensions (over 32) from Python code, which could let a malicious user cause a Denial of Service. NOTE: The vendor does not agree this is a vulneraility; In (very limited) circumstances a user may be able provoke the buffer overflow, the user is most likely already privileged to at least provoke denial of service by exhausting memory. Triggering this further requires the use of uncommon API (complicated structured dtypes), which is very unlikely to be available to an unprivileged user

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | numpy Debian 12.15 (bookworm) | 1:1.21.4-2 | [DEBIAN-CVE-2021-33430](https://patchblox.com/security/data/fix/linux/debian-cve-2021-33430.md) | Dec 17, 2021 |
| Linux | numpy Debian 13.5 (trixie) | 1:1.21.4-2 | [DEBIAN-CVE-2021-33430](https://patchblox.com/security/data/fix/linux/debian-cve-2021-33430.md) | Dec 17, 2021 |
| Linux | numpy Debian 14 | 1:1.21.4-2 | [DEBIAN-CVE-2021-33430](https://patchblox.com/security/data/fix/linux/debian-cve-2021-33430.md) | Dec 17, 2021 |
| Linux | python3-numpy Ubuntu 20.04 LTS (focal) | 1:1.17.4-5ubuntu3.1 | [python3-numpy 1:1.17.4-5ubuntu3.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-python3-numpy-1-1.17.4-5ubuntu3.1.md) | Dec 17, 2021 |

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