Security advisory

{
  "id": "e10d5add44c987496d26bfb06e169f4021acc3631912d2f4633435adce9a280e",
  "url": "https://osv.dev/vulnerability/CVE-2020-8159",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "CVE-2020-8159",
    "summary": "There is a vulnerability in actionpack_page-caching gem < v1.2.1 that allows an attacker to write arbitrary files to a web server, potentially resulting in remote code execution if the attacker can write unescaped ERB to a view.",
    "evidence": "osv:CVE-2020-8159",
    "products": [],
    "severity": "critical",
    "structured": {
      "id": "CVE-2020-8159",
      "aliases": [
        "CVE-2020-8159",
        "GHSA-mg5p-95m9-rmfp"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/rails/actionpack-action_caching",
              "type": "GIT",
              "events": [
                {
                  "introduced": "0"
                },
                {
                  "fixed": "6bce590e30d24db8e9eeb6692b66b19ab8999b1b"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "cpe": "cpe:2.3:a:rubyonrails:actionpack_page-caching:*:*:*:*:*:ruby:*:*",
                    "range": [
                      {
                        "introduced": "0"
                      },
                      {
                        "fixed": "1.2.1"
                      }
                    ],
                    "source": "CPE_RANGE"
                  }
                ]
              }
            }
          ],
          "versions": [
            "v1.2.0",
            "v1.1.1",
            "v1.1.0",
            "v1.0.0"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2020-8159.json"
          }
        },
        {
          "ranges": [
            {
              "repo": "https://github.com/rails/actionpack-page_caching",
              "type": "GIT",
              "events": [
                {
                  "introduced": "0"
                },
                {
                  "fixed": "066693b3e6a0f491179fedc3b4262f32b88a8872"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "cpe": "cpe:2.3:a:rubyonrails:actionpack_page-caching:*:*:*:*:*:ruby:*:*",
                    "range": [
                      {
                        "introduced": "0"
                      },
                      {
                        "fixed": "1.2.1"
                      }
                    ],
                    "source": "CPE_RANGE"
                  }
                ]
              }
            }
          ],
          "versions": [
            "v1.2.0",
            "v1.1.0",
            "v1.0.2",
            "v1.0.1",
            "v1.0.0"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2020-8159.json"
          }
        }
      ],
      "modified": "2026-10-24T10:30:49.198410298Z",
      "provider": "osv",
      "references": [
        "https://groups.google.com/forum/#%21topic/rubyonrails-security/CFRVkEytdP8",
        "https://lists.debian.org/debian-lts-announce/2021/07/msg00019.html"
      ],
      "provider_metadata": {
        "unresolved_ranges": [
          {
            "cpes": [
              "cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*"
            ],
            "vendor_product": "debian:debian_linux",
            "extracted_events": [
              {
                "range": [
                  {
                    "introduced": "9.0"
                  },
                  {
                    "last_affected": "9.0"
                  }
                ],
                "source": "CPE_STRING"
              }
            ]
          }
        ]
      }
    },
    "related_cves": [
      {
        "value": "CVE-2020-8159",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 436946,
  "published_at": "2020-05-12T13:15:13.25+00:00"
}