CVE-2017-20285 (GCVE-0-2017-20285)

Vulnerability from cvelistv5 – Published: 2026-10-05 06:49 – Updated: 2026-10-05 06:49
VLAI
Title
YAML versions before 1.30 for Perl allow a loaded document to trigger the DESTROY method of arbitrary classes
Summary
YAML versions before 1.30 for Perl allow a loaded document to trigger the DESTROY method of arbitrary classes. A perl/hash:Class tag blesses a hash into the class it names. The document supplies the object's fields, and Perl calls DESTROY when it goes out of scope. What DESTROY does depends on the classes the process has loaded. With File::Temp::Dir from core Perl, it can delete a directory tree the document names.
Severity
No CVSS data available.
CWE
  • CWE-502 - Deserialization of Untrusted Data
  • CWE-470 - Use of Externally-Controlled Input to Select Classes or Code ('Unsafe Reflection')
Assigner
References
Impacted products
Vendor Product Version CPE status
Affected: 0 , < 1.30 (custom)
Show details on NVD website
To clipboard 

{
  "containers": {
    "cna": {
      "affected": [
        {
          "collectionURL": "https://cpan.org/modules",
          "defaultStatus": "unaffected",
          "modules": [
            "YAML"
          ],
          "packageName": "YAML",
          "packageURL": "pkg:cpan/YAML",
          "programFiles": [
            "lib/YAML.pm",
            "lib/YAML/Loader.pm",
            "lib/YAML/Types.pm"
          ],
          "programRoutines": [
            {
              "name": "YAML::Loader::_parse_explicit"
            },
            {
              "name": "YAML::Type::code::yaml_load"
            },
            {
              "name": "YAML::Type::regexp::yaml_load"
            }
          ],
          "repo": "https://github.com/ingydotnet/yaml-pm",
          "versions": [
            {
              "lessThan": "1.30",
              "status": "affected",
              "version": "0",
              "versionType": "custom"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "YAML versions before 1.30 for Perl allow a loaded document to trigger the DESTROY method of arbitrary classes.\n\nA perl/hash:Class tag blesses a hash into the class it names. The document supplies the object\u0027s fields, and Perl calls DESTROY when it goes out of scope.\n\nWhat DESTROY does depends on the classes the process has loaded. With File::Temp::Dir from core Perl, it can delete a directory tree the document names."
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-502",
              "description": "CWE-502 Deserialization of Untrusted Data",
              "lang": "en",
              "type": "CWE"
            }
          ]
        },
        {
          "descriptions": [
            {
              "cweId": "CWE-470",
              "description": "CWE-470 Use of Externally-Controlled Input to Select Classes or Code (\u0027Unsafe Reflection\u0027)",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-10-05T06:49:17.583Z",
        "orgId": "9b29abf9-4ab0-4765-b253-1875cd9b441e",
        "shortName": "CPANSec"
      },
      "references": [
        {
          "tags": [
            "issue-tracking"
          ],
          "url": "https://github.com/ingydotnet/yaml-pm/issues/176"
        },
        {
          "tags": [
            "patch"
          ],
          "url": "https://github.com/ingydotnet/yaml-pm/commit/471314bbdcbd62077eea32755929122aa8bd00a3.patch"
        },
        {
          "tags": [
            "patch"
          ],
          "url": "https://github.com/ingydotnet/yaml-pm/commit/7736f38bd02e4f9f77d5468721e3be3d7b34a8ec.patch"
        },
        {
          "tags": [
            "release-notes"
          ],
          "url": "https://metacpan.org/release/TINITA/YAML-1.30/changes"
        }
      ],
      "solutions": [
        {
          "lang": "en",
          "value": "Upgrade to YAML 1.30 or later."
        }
      ],
      "source": {
        "discovery": "UNKNOWN"
      },
      "timeline": [
        {
          "lang": "en",
          "time": "2017-05-10T00:00:00.000Z",
          "value": "Issue reported."
        },
        {
          "lang": "en",
          "time": "2018-05-11T00:00:00.000Z",
          "value": "Version 1.25 released with the $YAML::LoadBlessed option."
        },
        {
          "lang": "en",
          "time": "2020-01-27T00:00:00.000Z",
          "value": "Version 1.30 released with the option defaulting to off."
        },
        {
          "lang": "en",
          "time": "2022-06-27T00:00:00.000Z",
          "value": "Issue added as CPANSA-YAML-2017-01 in the CPAN::Audit database."
        },
        {
          "lang": "en",
          "time": "2026-09-21T00:00:00.000Z",
          "value": "CVE number reserved."
        }
      ],
      "title": "YAML versions before 1.30 for Perl allow a loaded document to trigger the DESTROY method of arbitrary classes",
      "workarounds": [
        {
          "lang": "en",
          "value": "For deployments that cannot upgrade to YAML 1.30, set $YAML::LoadBlessed = 0 before loading untrusted input. The option exists from YAML 1.25."
        }
      ],
      "x_generator": {
        "engine": "cpansec-cna-tool 0.1"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "9b29abf9-4ab0-4765-b253-1875cd9b441e",
    "assignerShortName": "CPANSec",
    "cveId": "CVE-2017-20285",
    "datePublished": "2026-10-05T06:49:17.583Z",
    "dateReserved": "2026-09-21T21:18:28.499Z",
    "dateUpdated": "2026-10-05T06:49:17.583Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2017-20285",
      "date": "2026-10-05",
      "epss": "0.00184",
      "percentile": "0.07212"
    },
    "nvd": {
      "cve": {
        "affected": [
          {
            "affectedData": [
              {
                "collectionURL": "https://cpan.org/modules",
                "defaultStatus": "unaffected",
                "modules": [
                  "YAML"
                ],
                "packageName": "YAML",
                "packageURL": "pkg:cpan/YAML",
                "programFiles": [
                  "lib/YAML.pm",
                  "lib/YAML/Loader.pm",
                  "lib/YAML/Types.pm"
                ],
                "programRoutines": [
                  {
                    "name": "YAML::Loader::_parse_explicit"
                  },
                  {
                    "name": "YAML::Type::code::yaml_load"
                  },
                  {
                    "name": "YAML::Type::regexp::yaml_load"
                  }
                ],
                "repo": "https://github.com/ingydotnet/yaml-pm",
                "versions": [
                  {
                    "lessThan": "1.30",
                    "status": "affected",
                    "version": "0",
                    "versionType": "custom"
                  }
                ]
              }
            ],
            "source": "9b29abf9-4ab0-4765-b253-1875cd9b441e"
          }
        ],
        "cveTags": [],
        "descriptions": [
          {
            "lang": "en",
            "value": "YAML versions before 1.30 for Perl allow a loaded document to trigger the DESTROY method of arbitrary classes.\n\nA perl/hash:Class tag blesses a hash into the class it names. The document supplies the object\u0027s fields, and Perl calls DESTROY when it goes out of scope.\n\nWhat DESTROY does depends on the classes the process has loaded. With File::Temp::Dir from core Perl, it can delete a directory tree the document names."
          }
        ],
        "id": "CVE-2017-20285",
        "lastModified": "2026-10-05T07:16:29.017",
        "metrics": {},
        "published": "2026-10-05T07:16:29.017",
        "references": [
          {
            "source": "9b29abf9-4ab0-4765-b253-1875cd9b441e",
            "url": "https://github.com/ingydotnet/yaml-pm/commit/471314bbdcbd62077eea32755929122aa8bd00a3.patch"
          },
          {
            "source": "9b29abf9-4ab0-4765-b253-1875cd9b441e",
            "url": "https://github.com/ingydotnet/yaml-pm/commit/7736f38bd02e4f9f77d5468721e3be3d7b34a8ec.patch"
          },
          {
            "source": "9b29abf9-4ab0-4765-b253-1875cd9b441e",
            "url": "https://github.com/ingydotnet/yaml-pm/issues/176"
          },
          {
            "source": "9b29abf9-4ab0-4765-b253-1875cd9b441e",
            "url": "https://metacpan.org/release/TINITA/YAML-1.30/changes"
          }
        ],
        "sourceIdentifier": "9b29abf9-4ab0-4765-b253-1875cd9b441e",
        "vulnStatus": "Received",
        "weaknesses": [
          {
            "description": [
              {
                "lang": "en",
                "value": "CWE-470"
              },
              {
                "lang": "en",
                "value": "CWE-502"
              }
            ],
            "source": "9b29abf9-4ab0-4765-b253-1875cd9b441e",
            "type": "Secondary"
          }
        ]
      }
    },
    "redhat_vex": {
      "aggregate_severity": "Important",
      "current_release_date": "2026-10-05T09:03:44+00:00",
      "cve": "CVE-2017-20285",
      "id": "CVE-2017-20285",
      "initial_release_date": "2017-01-01T00:00:00+00:00",
      "product_status:known_affected": "5",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "perl-yaml: perl-yaml: Arbitrary destructor method execution via crafted YAML document",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2017/cve-2017-20285.json",
      "version": "3"
    }
  }
}



Log in or create an account to share your comment.




Tags
Taxonomy of the tags.





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

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • 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.



Related by attack behaviour

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.