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Medium

NumPy Buffer Overflow (Disputed)

  • Disclosed: 17.12.2021
  • Updated: 11.10.2026 11:20

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 vulnerability; 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.

Affected software

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PlatformPackageVulnerable versionsFixed in
Python (PyPI) numpy >= 1.9.0, < 1.21 1.21

References

CVSS score 5.3/10
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H
Weakness (CWE)
CWE-120
Platform
Python (PyPI)
Package
numpy
Disclosed
17.12.2021
Updated
11.10.2026 11:20

Sources and licenses

OSV / GitHub Advisory Database - PYSEC-2021-854 - PyPA Advisory Database; CC BY 4.0

OSV / GitHub Advisory Database - GHSA-6p56-wp2h-9hxr - CC BY 4.0

Vulnerability history: numpy

All published vulnerabilities of this package (Python (PyPI)), newest first. Shows whether this is a one-off slip or a package that needs watching.

Total entries
8
First → latest
08.2017 12.2021
Without a fix
0
Exploited in attacks
0

Severity breakdown

  • Critical 1
  • High 4
  • Medium 3

Disclosures per year

  1. Buffer overflow in the array_from_pyobj function of fortranobject.c in NumPy < 1.19, which allows attackers to conduct a Denial of Service attacks by carefully constructing an array with negative valu
    Medium · 5.5 CVE-2021-41496 < 1.19.0 1.19.0
  2. Null Pointer Dereference vulnerability exists in numpy.sort in NumPy &lt and 1.19 in the PyArray_DescrNew function due to missing return-value validation, which allows attackers to conduct DoS attacks
    High · 7.5 CVE-2021-41495 < 1.19.1 1.19.1
  3. Incomplete string comparison in the numpy.core component in NumPy1.9.x, which allows attackers to fail the APIs via constructing specific string objects.
    Medium · 5.3 CVE-2021-34141 >= 1.9.0, < 1.10.0 1.10.0
  4. NumPy Buffer Overflow (Disputed) this entry
    Medium · 5.3 CVE-2021-33430 >= 1.9.0, < 1.21 1.21
  5. Numpy Deserialization of Untrusted Data
    Critical · 9.8 CVE-2019-6446 < 1.16.3 1.16.3
  6. Numpy arbitrary file write via symlink attack
    High · 5.5 CVE-2014-1859 < 1.8.1 1.8.1
  7. Arbitrary file write in NumPy
    High · 5.5 CVE-2014-1858 < 1.8.1 1.8.1
  8. The numpy.pad function in Numpy 1.13.1 and older versions is missing input validation. An empty list or ndarray will stick into an infinite loop, which can allow attackers to cause a DoS attack.
    High · 7.5 CVE-2017-12852 < 1.13.3 1.13.3

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