Security advisory

{
  "id": "40f35a42ae8ad9b657dbae5f4c59a54bf4be54868f938888dfaae0de604f2c76",
  "url": "https://osv.dev/vulnerability/CVE-2026-8711",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "CVE-2026-8711",
    "summary": "NGINX JavaScript has a vulnerability when the js_fetch_proxy directive is configured with at least one client-controlled NGINX variable (for example, $http_*, $arg_*, $cookie_*) and a location invoking the ngx.fetch() operation from NGINX JavaScript. An unauthenticated attacker can exploit this vulnerability by sending crafted HTTP requests. This may cause a heap buffer overflow in the NGINX worker process leading to a restart. Additionally, attackers can execute code on systems with Address Space Layout Randomization (ASLR) disabled or when the attacker can bypass ASLR. Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.",
    "evidence": "osv:CVE-2026-8711",
    "products": [],
    "severity": "critical",
    "structured": {
      "id": "CVE-2026-8711",
      "aliases": [
        "CVE-2026-8711"
      ],
      "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/nginx/njs",
              "type": "GIT",
              "events": [
                {
                  "introduced": "927d38d8438e8b3b3db63af4d9f6324210fd5dab"
                },
                {
                  "fixed": "9ead4e71f74a27279f3212bdb6cadb0e86981a1b"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "cpe": "cpe:2.3:a:f5:njs:*:*:*:*:*:*:*:*",
                    "range": [
                      {
                        "introduced": "0.9.4"
                      },
                      {
                        "fixed": "0.9.9"
                      }
                    ],
                    "source": "CPE_RANGE"
                  }
                ]
              }
            }
          ],
          "versions": [
            "0.9.8",
            "0.9.7",
            "0.9.6",
            "0.9.5",
            "0.9.4"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-8711.json"
          }
        }
      ],
      "modified": "2026-10-24T10:30:19.542534668Z",
      "provider": "osv",
      "references": [
        "https://my.f5.com/manage/s/article/K000161307"
      ],
      "provider_metadata": {}
    },
    "related_cves": [
      {
        "value": "CVE-2026-8711",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 430043,
  "published_at": "2026-05-19T15:16:33.017+00:00"
}