CVE-2026-63209

{
  "etk_id": "ETK-2026-401",
  "cve_id": "CVE-2026-63209",
  "display_id": "CVE-2026-63209",
  "ghsa_id": "GHSA-259r-337f-4rfw",
  "euvd_id": "EUVD-2026-88977",
  "status": "published",
  "anchor_state": "anchored",
  "title": "Signed integer overflow in klauspost/compress s2 dictionaries",
  "summary": "The s2 dictionary handling in klauspost/compress versions through v1.18.6 is affected by a signed integer overflow. An attacker who can supply dictionary data to an application and cause that dictionary to be used for encoding can terminate the process.",
  "mitigation": "Upgrade klauspost/compress/s2 to v1.18.7 or later. Until upgraded, do not accept untrusted S2 dictionary data for use with the affected dictionary encoding path.",
  "vendor": "klauspost",
  "product": "klauspost:compress/s2",
  "affected": [
    {
      "affected_notes": [],
      "affected_ranges": [
        "<= v1.18.6"
      ],
      "ecosystem": "klauspost",
      "fixed_versions": [
        "v1.18.7"
      ],
      "package_name": "compress/s2",
      "purl": null
    }
  ],
  "cwes": [
    190
  ],
  "cvss_score": 7.5,
  "cvss_src": "cna_vendor",
  "cvss_vector": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
  "epss_score": 0.0037,
  "epss_percentile": 0.2888,
  "epss_asof": "2026-10-20",
  "automation": "deterministic",
  "check": false,
  "check_confidence_basis": null,
  "exploit": false,
  "pipeline_minutes": 10.503251733333334,
  "t0_at": "2026-09-29T14:58:53.366000+00:00",
  "signals": {
    "public_poc": {
      "at": "2026-06-30T11:23:20+00:00",
      "days": -91.14969173611111,
      "is_lower_bound": false,
      "measured_at": "2026-09-29T14:58:53.366000+00:00",
      "url": "https://github.com/klauspost/compress/security/advisories/GHSA-259r-337f-4rfw"
    },
    "trigger_signal": {
      "at": "2026-09-29T14:58:53.366000+00:00",
      "days": 0,
      "is_lower_bound": false,
      "measured_at": "2026-09-29T14:58:53.366000+00:00",
      "url": "https://github.com/klauspost/compress/security/advisories/GHSA-259r-337f-4rfw"
    }
  }
}