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ubuntu-cve-2021-41495
Vulnerability from osv_ubuntu
Published
2021-12-17 20:15
Modified
2025-09-08 16:47
Summary
Details

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 by repetitively creating sort arrays. NOTE: While correct that validation is missing, an error can only occur due to an exhaustion of memory. If the user can exhaust memory, they are already privileged. Further, it should be practically impossible to construct an attack which can target the memory exhaustion to occur at exactly this place

Severity
5.3 (Medium)
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H
N/A (UNKNOWN)
medium
References
To clipboard 

{
  "affected": [
    {
      "ecosystem_specific": {
        "availability": "No subscription required",
        "binaries": [
          {
            "binary_name": "python3-numpy",
            "binary_version": "1:1.17.4-5ubuntu3.1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:20.04:LTS",
        "name": "numpy",
        "purl": "pkg:deb/ubuntu/numpy@1:1.17.4-5ubuntu3.1?arch=source\u0026distro=focal"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "1:1.17.4-5ubuntu3.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1:1.17.3-0ubuntu2",
        "1:1.17.4-3ubuntu1",
        "1:1.17.4-3ubuntu2",
        "1:1.17.4-5ubuntu2",
        "1:1.17.4-5ubuntu3"
      ]
    },
    {
      "ecosystem_specific": {
        "availability": "No subscription required",
        "binaries": [
          {
            "binary_name": "python3-numpy",
            "binary_version": "1:1.21.5-1ubuntu22.04.1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:22.04:LTS",
        "name": "numpy",
        "purl": "pkg:deb/ubuntu/numpy@1:1.21.5-1ubuntu22.04.1?arch=source\u0026distro=jammy"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "1:1.21.5-1ubuntu22.04.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1:1.19.5-1ubuntu2",
        "1:1.19.5-1ubuntu3",
        "1:1.20.2-1ubuntu1",
        "1:1.21.4-2",
        "1:1.21.5-1",
        "1:1.21.5-1build2"
      ]
    }
  ],
  "aliases": [],
  "details": "Null Pointer Dereference vulnerability exists in numpy.sort in NumPy \u0026lt and 1.19 in the PyArray_DescrNew function due to missing return-value validation, which allows attackers to conduct DoS attacks by repetitively creating sort arrays. NOTE: While correct that validation is missing, an error can only occur due to an exhaustion of memory. If the user can exhaust memory, they are already privileged. Further, it should be practically impossible to construct an attack which can target the memory exhaustion to occur at exactly this place",
  "id": "UBUNTU-CVE-2021-41495",
  "modified": "2025-09-08T16:47:22Z",
  "published": "2021-12-17T20:15:00Z",
  "references": [
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2021-41495"
    },
    {
      "type": "REPORT",
      "url": "https://github.com/numpy/numpy/issues/19038"
    },
    {
      "type": "REPORT",
      "url": "https://github.com/numpy/numpy/pull/20984"
    },
    {
      "type": "REPORT",
      "url": "https://github.com/numpy/numpy/pull/20960"
    },
    {
      "type": "ADVISORY",
      "url": "https://ubuntu.com/security/notices/USN-5763-1"
    },
    {
      "type": "REPORT",
      "url": "https://www.cve.org/CVERecord?id=CVE-2021-41495"
    }
  ],
  "related": [
    "USN-5763-1"
  ],
  "schema_version": "1.7.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    },
    {
      "score": "medium",
      "type": "Ubuntu"
    }
  ],
  "upstream": [
    "CVE-2021-41495"
  ]
}



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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
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  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.


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Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.