Security advisory

{
  "id": "13500a95518a5686b3efc5210d4aa5fb41074f72c2db4fa7a4527701dbb23ed0",
  "url": "https://osv.dev/vulnerability/CVE-2018-21035",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "CVE-2018-21035",
    "summary": "In Qt through 5.14.1, the WebSocket implementation accepts up to 2GB for frames and 2GB for messages. Smaller limits cannot be configured. This makes it easier for attackers to cause a denial of service (memory consumption).",
    "evidence": "osv:CVE-2018-21035",
    "products": [],
    "severity": "high",
    "structured": {
      "id": "CVE-2018-21035",
      "aliases": [
        "CVE-2018-21035"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/qt/qt5",
              "type": "GIT",
              "events": [
                {
                  "introduced": "0"
                },
                {
                  "last_affected": "eac5e8f5c8b7f3c7de6bce0626c724cbeaa4a8a4"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "cpe": "cpe:2.3:a:qt:qt:*:*:*:*:*:*:*:*",
                    "range": [
                      {
                        "introduced": "0"
                      },
                      {
                        "last_affected": "5.14.1"
                      }
                    ],
                    "source": "CPE_RANGE"
                  }
                ]
              }
            }
          ],
          "versions": [
            "v5.14.1",
            "v5.14.0-beta3",
            "v5.14.0-beta2",
            "v5.14.0-beta1",
            "v5.14.0-alpha1",
            "v5.0.0-beta1"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2018-21035.json"
          }
        },
        {
          "ranges": [
            {
              "repo": "https://github.com/qt/qtbase",
              "type": "GIT",
              "events": [
                {
                  "introduced": "0"
                },
                {
                  "last_affected": "0ab53fbdda2fd7f24f45dcd52fbd195e282554da"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "cpe": "cpe:2.3:a:qt:qt:*:*:*:*:*:*:*:*",
                    "range": [
                      {
                        "introduced": "0"
                      },
                      {
                        "last_affected": "5.14.1"
                      }
                    ],
                    "source": "CPE_RANGE"
                  }
                ]
              }
            }
          ],
          "versions": [
            "v5.14.1",
            "v5.14.0-beta3",
            "v5.14.0-beta2",
            "v5.14.0-beta1",
            "v5.14.0-alpha1",
            "v5.0.0-beta2",
            "v5.0.0-beta1"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2018-21035.json"
          }
        }
      ],
      "modified": "2026-10-24T10:30:53.478888784Z",
      "provider": "osv",
      "references": [
        "https://codereview.qt-project.org/c/qt/qtwebsockets/+/284735",
        "https://bugreports.qt.io/browse/QTBUG-70693"
      ],
      "provider_metadata": {}
    },
    "related_cves": [
      {
        "value": "CVE-2018-21035",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 437932,
  "published_at": "2020-02-28T21:15:12.79+00:00"
}