Security advisory

{
  "id": "3071aea15a3824aa355889fc453aa6bc864adef919134dd49296bc41d9672db1",
  "url": "https://osv.dev/vulnerability/CVE-2021-42697",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "CVE-2021-42697",
    "summary": "Akka HTTP 10.1.x before 10.1.15 and 10.2.x before 10.2.7 can encounter stack exhaustion while parsing HTTP headers, which allows a remote attacker to conduct a Denial of Service attack by sending a User-Agent header with deeply nested comments.",
    "evidence": "osv:CVE-2021-42697",
    "products": [],
    "severity": "high",
    "structured": {
      "id": "CVE-2021-42697",
      "aliases": [
        "CVE-2021-42697",
        "GHSA-3hw2-h67c-wq66"
      ],
      "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/akka/akka-http",
              "type": "GIT",
              "events": [
                {
                  "introduced": "3bd4b8a9566a8de9ecd730b50552b580ba3fe4c2"
                },
                {
                  "fixed": "5243345ff8eeb2ad7663bbb2a1d6e217a725afda"
                },
                {
                  "introduced": "80ebb83d75f1c6c45ded2901efbe97dd43c2051d"
                },
                {
                  "fixed": "df3dbfbb8344844fdf4f9a2b3d8aebe3793bfc56"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "cpe": "cpe:2.3:a:akka:http_server:*:*:*:*:*:*:*:*",
                    "range": [
                      {
                        "introduced": "10.1.0"
                      },
                      {
                        "fixed": "10.1.15"
                      }
                    ],
                    "source": "CPE_RANGE"
                  },
                  {
                    "cpe": "cpe:2.3:a:akka:http_server:*:*:*:*:*:*:*:*",
                    "range": [
                      {
                        "introduced": "10.2.0"
                      },
                      {
                        "fixed": "10.2.7"
                      }
                    ],
                    "source": "CPE_RANGE"
                  }
                ]
              }
            }
          ],
          "versions": [
            "v10.2.6",
            "v10.2.5",
            "v10.2.5-M2",
            "v10.2.5-M1",
            "v10.1.14",
            "v10.2.4",
            "v10.2.3",
            "v10.2.2",
            "v10.1.13",
            "v10.2.1",
            "v10.2.0",
            "v10.1.12",
            "v10.1.11",
            "v10.1.10",
            "v10.1.9",
            "v10.1.8",
            "v10.1.7",
            "v10.1.6",
            "v10.1.5",
            "v10.1.4",
            "v10.1.3",
            "v10.1.2",
            "v10.1.1",
            "v10.1.0"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2021-42697.json"
          }
        }
      ],
      "modified": "2026-10-24T10:30:16.106179602Z",
      "provider": "osv",
      "references": [
        "https://akka.io/blog/",
        "https://akka.io/blog/news/2021/11/02/akka-http-10.2.7-released",
        "https://akka.io/blog/news/2021/11/22/akka-http-10.1.15-released",
        "https://doc.akka.io/docs/akka-http/current/security/2021-CVE-2021-42697-stack-overflow-parsing-user-agent.html"
      ],
      "provider_metadata": {}
    },
    "related_cves": [
      {
        "value": "CVE-2021-42697",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 429289,
  "published_at": "2021-11-02T22:15:08.957+00:00"
}