{
  "affected": [
    {
      "database_specific": {
        "last_known_affected_version_range": "\u003c= 0.3.3"
      },
      "package": {
        "ecosystem": "Go",
        "name": "github.com/juev/nebula-mesh"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "0.3.4"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [],
  "database_specific": {
    "cwe_ids": [
      "CWE-294"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-06-26T21:01:09Z",
    "nvd_published_at": null,
    "severity": "LOW"
  },
  "details": "`internal/api/pop/nonce.go:25,40,86` + `internal/api/server.go:38` \u2014 the signed-poll nonce cache is an in-process LRU sized at 65,536 entries. `internal/api/updates.go:31` sets `pollClockSkew = 5 * time.Minute` as the replay window.\n\n## Affected\nAll released versions through v0.3.0 that have shipped the ADR 0004 signed-poll path. (If this is gated behind a feature flag, on a side branch, or not yet on a release tag, please flag \u2014 this advisory may not apply to the released artifact yet.)\n\n## Threat model\nA captured signed-poll request can be replayed:\n\n1. **After any process restart** \u2014 the in-memory LRU is wiped, so the original nonce becomes \"unseen\" again. Replay succeeds if the original timestamp is still within the 5-minute skew.\n2. **After forced eviction** \u2014 an attacker with control of any single host can flood \u003e65,536 nonces under their own host_id, driving the global LRU to evict the victim\u0027s recorded nonce. Replay then succeeds.\n\nImpact is bounded: a replayed poll fetches the `/api/v1/agent/updates` body. That body can include a freshly-minted enrollment token if a rekey is pending (`updates.go:249-260`) \u2014 at which point the attacker holds a single-use token they can redeem under their own keypair.\n\n## Suggested fix\nTwo options, either acceptable:\n\n1. Persist nonces in SQLite keyed by `(host_id, nonce)` with `ON CONFLICT DO NOTHING`, retained for the timestamp-skew window. Adds one transactional INSERT per poll; bounded by the skew window (~5 min worth of rows server-wide).\n2. Per-host cap on the LRU instead of a global 65k cap, so one host cannot evict another\u0027s records. Combined with shorter skew (\u226430s) to bound the post-restart replay window.\n\nOption 1 is more robust; option 2 is lower-implementation-effort.",
  "id": "GHSA-v2jf-442r-6mjh",
  "modified": "2026-06-26T21:01:09Z",
  "published": "2026-06-26T21:01:09Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/juev/nebula-mesh/security/advisories/GHSA-v2jf-442r-6mjh"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/juev/nebula-mesh"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:U",
      "type": "CVSS_V4"
    }
  ],
  "summary": "nebula-mesh: Signed-poll nonce LRU is in-memory and bounded; replay survives restart + eviction"
}