Security advisory

{
  "id": "d832f7bc6e4bb3dd2e191b2218bc31452306b82841228ecbbb9866dbb5d87e9d",
  "url": "https://osv.dev/vulnerability/CVE-2021-39286",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "CVE-2021-39286",
    "summary": "Webrecorder pywb before 2.6.0 allows XSS because it does not ensure that Jinja2 templates are autoescaped.",
    "evidence": "osv:CVE-2021-39286",
    "products": [],
    "severity": "medium",
    "structured": {
      "id": "CVE-2021-39286",
      "aliases": [
        "CVE-2021-39286",
        "GHSA-947x-pv47-pp3q",
        "PYSEC-2021-120"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/webrecorder/pywb",
              "type": "GIT",
              "events": [
                {
                  "introduced": "0"
                },
                {
                  "fixed": "96de80f83e2e18a333f488d54d21d98dce3b9433"
                },
                {
                  "fixed": "f7bd84cdacdd665ff73ae8d09a202f60be2ebae9"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "cpe": "cpe:2.3:a:webrecorder:pywb:*:*:*:*:*:*:*:*",
                    "range": [
                      {
                        "introduced": "0"
                      },
                      {
                        "fixed": "2.6.0"
                      }
                    ],
                    "source": "CPE_RANGE"
                  },
                  {
                    "range": [
                      {
                        "fixed": "f7bd84cdacdd665ff73ae8d09a202f60be2ebae9"
                      }
                    ],
                    "source": "REFERENCES_COMMIT"
                  }
                ]
              }
            }
          ],
          "versions": [
            "v-2.6.0b0",
            "v-2.5.0",
            "v-2.4.2",
            "v-2.4.1",
            "v-2.4.0",
            "v-2.4.0-rc7",
            "v-2.4.0-rc5",
            "v-2.4.0rc4",
            "v-2.4.0-rc2",
            "v-2.4.0-rc1",
            "v-2.4.0-rc0",
            "v-2.3.1",
            "v-2.3.0",
            "v-2.2.20190410",
            "v-2.2.20190311",
            "v-2.2.20190227",
            "0.32.0",
            "0.11.0",
            "0.10.10",
            "0.10.9.1",
            "0.10.9",
            "0.10.8",
            "0.10.5",
            "0.10.1",
            "0.9.5",
            "0.9.0",
            "0.8.0",
            "0.7.1",
            "0.7.0",
            "0.6.2",
            "0.6.0",
            "0.4.0",
            "0.3.0",
            "0.2.2"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2021-39286.json"
          }
        }
      ],
      "modified": "2026-10-20T10:53:54.000312324Z",
      "provider": "osv",
      "references": [
        "https://github.com/webrecorder/pywb/compare/v-2.5.0...v-2.6.0",
        "https://github.com/webrecorder/pywb/commit/f7bd84cdacdd665ff73ae8d09a202f60be2ebae9"
      ],
      "provider_metadata": {}
    },
    "related_cves": [
      {
        "value": "CVE-2021-39286",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 384739,
  "published_at": "2021-08-18T18:15:08.177+00:00"
}