Vector: Unauthenticated denial of service in the `logstash` source via nested compressed frames (stack exhaustion and decompression amplification).

{
  "id": "96b488e5306cbffba049b1d1f90284bf28e0a78760ec3ff8f377480809d71b8d",
  "url": "https://osv.dev/vulnerability/CVE-2026-77620",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "Vector: Unauthenticated denial of service in the `logstash` source via nested compressed frames (stack exhaustion and decompression amplification).",
    "summary": "Vector is a high-performance observability data pipeline. From 0.15.0 until 0.57.0, the logstash source feeds each decompressed frame back into its decoder without limiting nested compression depth. An unauthenticated remote peer that can reach the default 0.0.0.0:5044 listener can send many nested compressed frames, causing recursive decoding that exhausts the worker thread stack and aborts the process. The same nested construction amplifies decompressed input, and process termination can halt log ingestion for every tenant on a shared pipeline. This issue is fixed in version 0.57.0.",
    "evidence": "osv:CVE-2026-77620",
    "products": [],
    "severity": "high",
    "structured": {
      "id": "CVE-2026-77620",
      "aliases": [
        "CVE-2026-77620",
        "GHSA-qp6f-fpfx-4gg6"
      ],
      "metrics": [
        {
          "type": "CVSS_V4",
          "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/vectordotdev/vector",
              "type": "GIT",
              "events": [
                {
                  "introduced": "994d81239a9b5ea4eae3e92530e601629b593cc6"
                },
                {
                  "fixed": "8832452f57afb536ea0de53a093f9fd1b669ccec"
                },
                {
                  "fixed": "57fed991083c9a43d5fda2d5b3bf4718aedf6526"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "range": [
                      {
                        "introduced": "0.15.0"
                      },
                      {
                        "fixed": "0.57.0"
                      }
                    ],
                    "source": "AFFECTED_FIELD",
                    "strategy": "StringRangeExpression"
                  },
                  {
                    "range": [
                      {
                        "fixed": "57fed991083c9a43d5fda2d5b3bf4718aedf6526"
                      }
                    ],
                    "source": "REFERENCES_COMMIT"
                  },
                  {
                    "range": [
                      {
                        "fixed": "8832452f57afb536ea0de53a093f9fd1b669ccec"
                      }
                    ],
                    "source": "REFERENCES_TAG",
                    "original_tag": "v0.57.0"
                  }
                ]
              }
            }
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-77620.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:27.276493005Z",
      "provider": "osv",
      "references": [
        "https://github.com/vectordotdev/vector/releases/tag/v0.57.0",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/77xxx/CVE-2026-77620.json",
        "https://github.com/vectordotdev/vector/security/advisories/GHSA-qp6f-fpfx-4gg6",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-77620",
        "https://github.com/vectordotdev/vector/commit/57fed991083c9a43d5fda2d5b3bf4718aedf6526",
        "https://github.com/vectordotdev/vector/pull/25825"
      ],
      "provider_metadata": {
        "cwe_ids": [
          "CWE-409"
        ],
        "cna_assigner": "GitHub_M",
        "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/77xxx/CVE-2026-77620.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-77620",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 493885,
  "published_at": "2026-09-22T15:18:21.102+00:00"
}