ckeditor — security advisory

{
  "id": "a2087135f865b9c2ebe3693308a34ea219ac689d48e5c1d3232a8b62a61fe5b0",
  "url": "https://osv.dev/vulnerability/DEBIAN-CVE-2021-26271",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "DEBIAN-CVE-2021-26271",
    "summary": "It was possible to execute a ReDoS-type attack inside CKEditor 4 before 4.16 by persuading a victim to paste crafted text into the Styles input of specific dialogs (in the Advanced Tab for Dialogs plugin).",
    "evidence": "osv:DEBIAN-CVE-2021-26271",
    "products": [
      {
        "name": {
          "value": "ckeditor",
          "evidence": "/affected/0/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [
          {
            "value": "4.16.0+dfsg-1",
            "evidence": "/affected/0/ranges"
          }
        ],
        "affected_versions": []
      }
    ],
    "severity": "medium",
    "structured": {
      "id": "DEBIAN-CVE-2021-26271",
      "aliases": [
        "DEBIAN-CVE-2021-26271"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "0"
                },
                {
                  "fixed": "4.16.0+dfsg-1"
                }
              ]
            }
          ],
          "package": {
            "name": "ckeditor",
            "purl": "pkg:deb/debian/ckeditor?arch=source&distro=bookworm",
            "ecosystem": "Debian:12"
          },
          "database_specific": {
            "source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2021-26271.json"
          },
          "ecosystem_specific": {
            "urgency": "not yet assigned"
          }
        }
      ],
      "modified": "2026-10-23T18:03:02.979957182Z",
      "provider": "osv",
      "upstream": [
        "CVE-2021-26271"
      ],
      "references": [
        "https://security-tracker.debian.org/tracker/CVE-2021-26271"
      ]
    },
    "related_cves": [
      {
        "value": "CVE-2021-26271",
        "evidence": "/upstream"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 420219,
  "published_at": "2021-01-26T21:15:12.86+00:00"
}