ubuntu-cve-2021-45444
Vulnerability from osv_ubuntu
Published
2022-02-14 12:15
Modified
2026-04-22 07:40
Summary
Details

In zsh before 5.8.1, an attacker can achieve code execution if they control a command output inside the prompt, as demonstrated by a %F argument. This occurs because of recursive PROMPT_SUBST expansion.

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

{
  "affected": [
    {
      "ecosystem_specific": {
        "availability": "Available with Ubuntu Pro (Infra-only): https://ubuntu.com/pro",
        "binaries": [
          {
            "binary_name": "zsh",
            "binary_version": "5.1.1-1ubuntu2.3+esm1"
          },
          {
            "binary_name": "zsh-common",
            "binary_version": "5.1.1-1ubuntu2.3+esm1"
          },
          {
            "binary_name": "zsh-static",
            "binary_version": "5.1.1-1ubuntu2.3+esm1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:16.04:LTS",
        "name": "zsh",
        "purl": "pkg:deb/ubuntu/zsh@5.1.1-1ubuntu2.3+esm1?arch=source\u0026distro=esm-infra/xenial"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "5.1.1-1ubuntu2.3+esm1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "5.1.1-1ubuntu1",
        "5.1.1-1ubuntu2",
        "5.1.1-1ubuntu2.1",
        "5.1.1-1ubuntu2.2",
        "5.1.1-1ubuntu2.3"
      ]
    },
    {
      "ecosystem_specific": {
        "availability": "No subscription required",
        "binaries": [
          {
            "binary_name": "zsh",
            "binary_version": "5.4.2-3ubuntu3.2"
          },
          {
            "binary_name": "zsh-common",
            "binary_version": "5.4.2-3ubuntu3.2"
          },
          {
            "binary_name": "zsh-static",
            "binary_version": "5.4.2-3ubuntu3.2"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:18.04:LTS",
        "name": "zsh",
        "purl": "pkg:deb/ubuntu/zsh@5.4.2-3ubuntu3.2?arch=source\u0026distro=bionic"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "5.4.2-3ubuntu3.2"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "5.2-5ubuntu1",
        "5.4.2-3ubuntu1",
        "5.4.2-3ubuntu2",
        "5.4.2-3ubuntu3",
        "5.4.2-3ubuntu3.1"
      ]
    },
    {
      "ecosystem_specific": {
        "availability": "No subscription required",
        "binaries": [
          {
            "binary_name": "zsh",
            "binary_version": "5.8-3ubuntu1.1"
          },
          {
            "binary_name": "zsh-common",
            "binary_version": "5.8-3ubuntu1.1"
          },
          {
            "binary_name": "zsh-static",
            "binary_version": "5.8-3ubuntu1.1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:20.04:LTS",
        "name": "zsh",
        "purl": "pkg:deb/ubuntu/zsh@5.8-3ubuntu1.1?arch=source\u0026distro=focal"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "5.8-3ubuntu1.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "5.7.1-1ubuntu2",
        "5.8-2ubuntu2",
        "5.8-3ubuntu1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "zsh",
            "binary_version": "5.8.1-1"
          },
          {
            "binary_name": "zsh-common",
            "binary_version": "5.8.1-1"
          },
          {
            "binary_name": "zsh-static",
            "binary_version": "5.8.1-1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:22.04:LTS",
        "name": "zsh",
        "purl": "pkg:deb/ubuntu/zsh@5.8.1-1?arch=source\u0026distro=jammy"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "5.8-6build1",
        "5.8-10",
        "5.8.1-1"
      ]
    }
  ],
  "aliases": [],
  "details": "In zsh before 5.8.1, an attacker can achieve code execution if they control a command output inside the prompt, as demonstrated by a %F argument. This occurs because of recursive PROMPT_SUBST expansion.",
  "id": "UBUNTU-CVE-2021-45444",
  "modified": "2026-04-22T07:40:12Z",
  "published": "2022-02-14T12:15:00Z",
  "references": [
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2021-45444"
    },
    {
      "type": "REPORT",
      "url": "https://sourceforge.net/p/zsh/code/ci/c187154f47697cdbf822c2f9d714d570ed4a0fd1/"
    },
    {
      "type": "REPORT",
      "url": "https://sourceforge.net/p/zsh/code/ci/fdb8b0ce6244ff26bf55e0fd825310a58d0d3156/"
    },
    {
      "type": "REPORT",
      "url": "https://sourceforge.net/p/zsh/code/ci/bdc4d70a7e033b754e68a8659a037ea0fc5f38de/"
    },
    {
      "type": "ADVISORY",
      "url": "https://ubuntu.com/security/notices/USN-5325-1"
    },
    {
      "type": "REPORT",
      "url": "https://www.cve.org/CVERecord?id=CVE-2021-45444"
    }
  ],
  "related": [
    "USN-5325-1"
  ],
  "schema_version": "1.7.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    },
    {
      "score": "low",
      "type": "Ubuntu"
    }
  ],
  "upstream": [
    "CVE-2021-45444"
  ]
}



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