Sliver has a DNS C2 OTP Bypass Allows Unauthenticated Session Flooding and Denial of Service

{
  "id": "132c586f742c83e031f85fed1ebb1da862dca8dde5b2701694d404b4d106e101",
  "url": "https://osv.dev/vulnerability/CVE-2026-25791",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "Sliver has a DNS C2 OTP Bypass Allows Unauthenticated Session Flooding and Denial of Service",
    "summary": "Sliver is a command and control framework that uses a custom Wireguard netstack. Prior to 1.7.0, the DNS C2 listener accepts unauthenticated TOTP bootstrap messages and allocates server-side DNS sessions without validating OTP values, even when EnforceOTP is enabled. Because sessions are stored without a cleanup/expiry path in this flow, an unauthenticated remote actor can repeatedly create sessions and drive memory exhaustion. This vulnerability is fixed in 1.7.0.",
    "evidence": "osv:CVE-2026-25791",
    "products": [],
    "severity": "high",
    "structured": {
      "id": "CVE-2026-25791",
      "aliases": [
        "CVE-2026-25791",
        "GHSA-wxrw-gvg8-fqjp",
        "GO-2026-4466"
      ],
      "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/bishopfox/sliver",
              "type": "GIT",
              "events": [
                {
                  "introduced": "0"
                },
                {
                  "fixed": "0bef5491dcca31485962e49cbf15cdda8c37a3f7"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "range": [
                      {
                        "introduced": "0"
                      },
                      {
                        "fixed": "1.7.0"
                      }
                    ],
                    "source": "AFFECTED_FIELD",
                    "strategy": "StringRangeExpression"
                  },
                  {
                    "range": [
                      {
                        "fixed": "0bef5491dcca31485962e49cbf15cdda8c37a3f7"
                      }
                    ],
                    "source": "REFERENCES_TAG",
                    "original_tag": "v1.7.0"
                  },
                  {
                    "cpe": "cpe:2.3:a:bishopfox:sliver:*:*:*:*:*:*:*:*",
                    "range": [
                      {
                        "introduced": "0"
                      },
                      {
                        "fixed": "1.7.0"
                      }
                    ],
                    "source": "CPE_RANGE"
                  }
                ]
              }
            }
          ],
          "versions": [
            "v1.6.11",
            "v1.6.10",
            "v1.6.9",
            "v1.6.8",
            "v1.6.7",
            "v1.6.6",
            "v1.6.5",
            "v1.6.4",
            "v1.6.3",
            "v1.6.2",
            "v1.6.1",
            "v1.6.0",
            "v1.5.30",
            "v1.5.29",
            "v1.5.28",
            "v1.5.27",
            "v1.5.26",
            "v1.5.25",
            "v1.5.23",
            "v1.5.24",
            "v1.5.22",
            "v1.5.21",
            "v1.5.20",
            "v1.5.19",
            "v1.5.18",
            "v1.5.17",
            "v1.5.16",
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            "v1.5.6",
            "v1.5.5",
            "v1.5.4",
            "v1.5.3",
            "v1.5.2",
            "v1.5.1",
            "v1.5.0",
            "v1.4.21",
            "v1.4.20",
            "v1.4.19",
            "v1.4.18",
            "v1.4.17",
            "v1.4.16",
            "v1.4.15",
            "v1.4.14",
            "v1.4.13",
            "v1.4.12",
            "v1.4.10",
            "v1.4.9",
            "v1.4.8",
            "v1.4.6",
            "v1.4.7",
            "v1.4.5",
            "v1.4.4",
            "v1.4.3",
            "v1.4.2",
            "v1.4.1",
            "v1.4.0",
            "v1.3.1",
            "v1.3.0",
            "v1.2.1",
            "v1.2.0",
            "v1.1.0",
            "v1.1.1",
            "v1.0.8-beta",
            "v1.0.7-beta",
            "v1.0.6-beta",
            "v1.0.3-beta",
            "v1.0.2-beta",
            "v1.0.0-beta",
            "v0.0.6-alpha",
            "v0.0.3-alpha",
            "v0.0.2-alpha",
            "v0.0.1-alpha"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-25791.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:37.090672256Z",
      "provider": "osv",
      "references": [
        "https://github.com/BishopFox/sliver/releases/tag/v1.7.0",
        "https://github.com/BishopFox/sliver/security/advisories/GHSA-wxrw-gvg8-fqjp",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/25xxx/CVE-2026-25791.json",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-25791"
      ],
      "provider_metadata": {
        "cwe_ids": [
          "CWE-306",
          "CWE-400"
        ],
        "cna_assigner": "GitHub_M",
        "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/25xxx/CVE-2026-25791.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-25791",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 504252,
  "published_at": "2026-02-09T20:34:31.144+00:00"
}