{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "extracted_events": [
              {
                "range": [
                  {
                    "introduced": "4.15.0"
                  },
                  {
                    "fixed": "4.16.1"
                  }
                ],
                "source": "AFFECTED_FIELD",
                "strategy": "StringRangeExpression"
              },
              {
                "range": [
                  {
                    "introduced": "5.0.0"
                  },
                  {
                    "fixed": "5.4.1"
                  }
                ],
                "source": "AFFECTED_FIELD",
                "strategy": "StringRangeExpression"
              },
              {
                "range": [
                  {
                    "fixed": "1855061e572ae9dab727c811d8382f266bfbaaec"
                  }
                ],
                "source": "REFERENCES_COMMIT"
              },
              {
                "range": [
                  {
                    "fixed": "3fb0ba7e17645bb65611e2a08875d0a2f65c421f"
                  }
                ],
                "source": "REFERENCES_COMMIT"
              },
              {
                "original_tag": "v4.16.1",
                "range": [
                  {
                    "fixed": "600b9855dfbcb22c7e643e43ce397d5248e882b2"
                  }
                ],
                "source": "REFERENCES_TAG"
              },
              {
                "original_tag": "v5.4.1",
                "range": [
                  {
                    "fixed": "a6a9673a54d2c719ceb32ce6a929d35483acfb2b"
                  }
                ],
                "source": "REFERENCES_TAG"
              }
            ]
          },
          "events": [
            {
              "introduced": "482bb46fe5c7eb7c9fd7bec7d3128433dea21bee"
            },
            {
              "fixed": "600b9855dfbcb22c7e643e43ce397d5248e882b2"
            },
            {
              "introduced": "9500f2745481e2dff1313e2e6734c488e80c13fb"
            },
            {
              "fixed": "a6a9673a54d2c719ceb32ce6a929d35483acfb2b"
            },
            {
              "fixed": "1855061e572ae9dab727c811d8382f266bfbaaec"
            },
            {
              "fixed": "3fb0ba7e17645bb65611e2a08875d0a2f65c421f"
            }
          ],
          "repo": "https://github.com/labstack/echo",
          "type": "GIT"
        }
      ]
    }
  ],
  "aliases": [
    "GHSA-9969-6676-49h5"
  ],
  "database_specific": {
    "cna_assigner": "GitHub_M",
    "cwe_ids": [
      "CWE-772"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/118xxx/CVE-2026-118262.json"
  },
  "details": "Echo is a Go web framework. From 4.15.0 until 4.16.1 and 5.4.1, Echo's Proxy middleware can retain a handler, copy goroutines, and network connections after a WebSocket client disconnects when the upstream keeps its connection open. The raw proxy waits for both copy directions without reliably closing the peer connection when one direction ends, including when a rejected upgrade response uses HTTP keep-alive. Repeated connections can accumulate resources and cause denial of service, depending on proxy-route accessibility, upstream behavior, and connection deadlines. This issue is fixed in 4.16.1 and 5.4.1.",
  "id": "CVE-2026-118262",
  "modified": "2026-10-29T10:30:33.957259566Z",
  "published": "2026-10-28T19:00:12.315Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/118xxx/CVE-2026-118262.json"
    },
    {
      "type": "FIX",
      "url": "https://github.com/labstack/echo/commit/1855061e572ae9dab727c811d8382f266bfbaaec"
    },
    {
      "type": "FIX",
      "url": "https://github.com/labstack/echo/commit/3fb0ba7e17645bb65611e2a08875d0a2f65c421f"
    },
    {
      "type": "WEB",
      "url": "https://github.com/labstack/echo/releases/tag/v4.16.1"
    },
    {
      "type": "WEB",
      "url": "https://github.com/labstack/echo/releases/tag/v5.4.1"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/labstack/echo/security/advisories/GHSA-9969-6676-49h5"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-118262"
    }
  ],
  "schema_version": "1.9.2",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N",
      "type": "CVSS_V4"
    }
  ],
  "summary": "Echo: WebSocket proxy can retain connections and handlers after client disconnect"
}