ubuntu-cve-2021-28651
Vulnerability from osv_ubuntu
Published
2021-05-27 12:15
Modified
2025-09-08 16:47
Summary
Details

An issue was discovered in Squid before 4.15 and 5.x before 5.0.6. Due to a buffer-management bug, it allows a denial of service. When resolving a request with the urn: scheme, the parser leaks a small amount of memory. However, there is an unspecified attack methodology that can easily trigger a large amount of memory consumption.

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

{
  "affected": [
    {
      "ecosystem_specific": {
        "availability": "Available with Ubuntu Pro (Infra-only): https://ubuntu.com/pro",
        "binaries": [
          {
            "binary_name": "squid",
            "binary_version": "3.5.12-1ubuntu7.16+esm3"
          },
          {
            "binary_name": "squid-cgi",
            "binary_version": "3.5.12-1ubuntu7.16+esm3"
          },
          {
            "binary_name": "squid-common",
            "binary_version": "3.5.12-1ubuntu7.16+esm3"
          },
          {
            "binary_name": "squid-purge",
            "binary_version": "3.5.12-1ubuntu7.16+esm3"
          },
          {
            "binary_name": "squid3",
            "binary_version": "3.5.12-1ubuntu7.16+esm3"
          },
          {
            "binary_name": "squidclient",
            "binary_version": "3.5.12-1ubuntu7.16+esm3"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:16.04:LTS",
        "name": "squid3",
        "purl": "pkg:deb/ubuntu/squid3@3.5.12-1ubuntu7.16+esm3?arch=source\u0026distro=esm-infra/xenial"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "3.5.12-1ubuntu7.16+esm3"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "3.3.8-1ubuntu16",
        "3.3.8-1ubuntu17",
        "3.5.12-1ubuntu6",
        "3.5.12-1ubuntu7",
        "3.5.12-1ubuntu7.1",
        "3.5.12-1ubuntu7.2",
        "3.5.12-1ubuntu7.3",
        "3.5.12-1ubuntu7.4",
        "3.5.12-1ubuntu7.5",
        "3.5.12-1ubuntu7.6",
        "3.5.12-1ubuntu7.7",
        "3.5.12-1ubuntu7.8",
        "3.5.12-1ubuntu7.9",
        "3.5.12-1ubuntu7.10",
        "3.5.12-1ubuntu7.11",
        "3.5.12-1ubuntu7.12",
        "3.5.12-1ubuntu7.13",
        "3.5.12-1ubuntu7.14",
        "3.5.12-1ubuntu7.15",
        "3.5.12-1ubuntu7.16",
        "3.5.12-1ubuntu7.16+esm1",
        "3.5.12-1ubuntu7.16+esm2"
      ]
    },
    {
      "ecosystem_specific": {
        "availability": "No subscription required",
        "binaries": [
          {
            "binary_name": "squid",
            "binary_version": "3.5.27-1ubuntu1.11"
          },
          {
            "binary_name": "squid-cgi",
            "binary_version": "3.5.27-1ubuntu1.11"
          },
          {
            "binary_name": "squid-common",
            "binary_version": "3.5.27-1ubuntu1.11"
          },
          {
            "binary_name": "squid-purge",
            "binary_version": "3.5.27-1ubuntu1.11"
          },
          {
            "binary_name": "squid3",
            "binary_version": "3.5.27-1ubuntu1.11"
          },
          {
            "binary_name": "squidclient",
            "binary_version": "3.5.27-1ubuntu1.11"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:18.04:LTS",
        "name": "squid3",
        "purl": "pkg:deb/ubuntu/squid3@3.5.27-1ubuntu1.11?arch=source\u0026distro=bionic"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "3.5.27-1ubuntu1.11"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "3.5.23-5ubuntu1",
        "3.5.23-5ubuntu2",
        "3.5.27-1ubuntu1",
        "3.5.27-1ubuntu1.1",
        "3.5.27-1ubuntu1.2",
        "3.5.27-1ubuntu1.3",
        "3.5.27-1ubuntu1.4",
        "3.5.27-1ubuntu1.5",
        "3.5.27-1ubuntu1.6",
        "3.5.27-1ubuntu1.7",
        "3.5.27-1ubuntu1.8",
        "3.5.27-1ubuntu1.9",
        "3.5.27-1ubuntu1.10"
      ]
    },
    {
      "ecosystem_specific": {
        "availability": "No subscription required",
        "binaries": [
          {
            "binary_name": "squid",
            "binary_version": "4.10-1ubuntu1.4"
          },
          {
            "binary_name": "squid-cgi",
            "binary_version": "4.10-1ubuntu1.4"
          },
          {
            "binary_name": "squid-common",
            "binary_version": "4.10-1ubuntu1.4"
          },
          {
            "binary_name": "squid-purge",
            "binary_version": "4.10-1ubuntu1.4"
          },
          {
            "binary_name": "squidclient",
            "binary_version": "4.10-1ubuntu1.4"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:20.04:LTS",
        "name": "squid",
        "purl": "pkg:deb/ubuntu/squid@4.10-1ubuntu1.4?arch=source\u0026distro=focal"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "4.10-1ubuntu1.4"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "4.8-1ubuntu2",
        "4.8-1ubuntu3",
        "4.9-2ubuntu1",
        "4.9-2ubuntu2",
        "4.9-2ubuntu3",
        "4.9-2ubuntu4",
        "4.10-1ubuntu1",
        "4.10-1ubuntu1.1",
        "4.10-1ubuntu1.2",
        "4.10-1ubuntu1.3"
      ]
    }
  ],
  "aliases": [],
  "details": "An issue was discovered in Squid before 4.15 and 5.x before 5.0.6. Due to a buffer-management bug, it allows a denial of service. When resolving a request with the urn: scheme, the parser leaks a small amount of memory. However, there is an unspecified attack methodology that can easily trigger a large amount of memory consumption.",
  "id": "UBUNTU-CVE-2021-28651",
  "modified": "2025-09-08T16:47:03Z",
  "published": "2021-05-27T12:15:00Z",
  "references": [
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2021-28651"
    },
    {
      "type": "REPORT",
      "url": "https://github.com/squid-cache/squid/security/advisories/GHSA-ch36-9jhx-phm4"
    },
    {
      "type": "ADVISORY",
      "url": "https://ubuntu.com/security/notices/USN-4981-1"
    },
    {
      "type": "REPORT",
      "url": "https://www.cve.org/CVERecord?id=CVE-2021-28651"
    },
    {
      "type": "ADVISORY",
      "url": "https://ubuntu.com/security/notices/USN-6857-1"
    }
  ],
  "related": [
    "USN-4981-1",
    "USN-6857-1"
  ],
  "schema_version": "1.7.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    },
    {
      "score": "medium",
      "type": "Ubuntu"
    }
  ],
  "upstream": [
    "CVE-2021-28651"
  ]
}



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