Security advisory

{
  "id": "51f63fd685ce45f56d6fdc53a2eeaec04bb3032596eb3bb28be15a38b89cac5f",
  "url": "https://osv.dev/vulnerability/CVE-2020-6017",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "CVE-2020-6017",
    "summary": "Valve's Game Networking Sockets prior to version v1.2.0 improperly handles long unreliable segments in function SNP_ReceiveUnreliableSegment() when configured to support plain-text messages, leading to a Heap-Based Buffer Overflow and resulting in a memory corruption and possibly even a remote code execution.",
    "evidence": "osv:CVE-2020-6017",
    "products": [],
    "severity": "critical",
    "structured": {
      "id": "CVE-2020-6017",
      "aliases": [
        "CVE-2020-6017"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/valvesoftware/gamenetworkingsockets",
              "type": "GIT",
              "events": [
                {
                  "introduced": "0"
                },
                {
                  "fixed": "5fe10494e27be722d18c443dc70f851541e5d554"
                },
                {
                  "fixed": "e0c86dcb9139771db3db0cfdb1fb8bef0af19c43"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "cpe": "cpe:2.3:a:valvesoftware:game_networking_sockets:*:*:*:*:*:*:*:*",
                    "range": [
                      {
                        "introduced": "0"
                      },
                      {
                        "fixed": "1.2.0"
                      }
                    ],
                    "source": "CPE_RANGE"
                  },
                  {
                    "range": [
                      {
                        "fixed": "e0c86dcb9139771db3db0cfdb1fb8bef0af19c43"
                      }
                    ],
                    "source": "REFERENCES_COMMIT"
                  }
                ]
              }
            }
          ],
          "versions": [
            "v1.1.0",
            "1.0.0"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2020-6017.json",
            "vanir_signatures": [
              {
                "id": "CVE-2020-6017-52d0820b",
                "digest": {
                  "length": 3309,
                  "function_hash": "112637649671998602830295864296836629670"
                },
                "source": "https://github.com/valvesoftware/gamenetworkingsockets/commit/e0c86dcb9139771db3db0cfdb1fb8bef0af19c43",
                "target": {
                  "file": "src/steamnetworkingsockets/clientlib/steamnetworkingsockets_snp.cpp",
                  "function": "CSteamNetworkConnectionBase::SNP_SendMessage"
                },
                "deprecated": false,
                "signature_type": "Function",
                "signature_version": "v1"
              },
              {
                "id": "CVE-2020-6017-7b1af979",
                "digest": {
                  "threshold": 0.9,
                  "line_hashes": [
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                    "51364348852482573533383862603153250368"
                  ]
                },
                "source": "https://github.com/valvesoftware/gamenetworkingsockets/commit/e0c86dcb9139771db3db0cfdb1fb8bef0af19c43",
                "target": {
                  "file": "src/steamnetworkingsockets/clientlib/steamnetworkingsockets_snp.cpp"
                },
                "deprecated": false,
                "signature_type": "Line",
                "signature_version": "v1"
              },
              {
                "id": "CVE-2020-6017-b5b8abe7",
                "digest": {
                  "threshold": 0.9,
                  "line_hashes": [
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                },
                "source": "https://github.com/valvesoftware/gamenetworkingsockets/commit/e0c86dcb9139771db3db0cfdb1fb8bef0af19c43",
                "target": {
                  "file": "src/steamnetworkingsockets/clientlib/steamnetworkingsockets_snp.h"
                },
                "deprecated": false,
                "signature_type": "Line",
                "signature_version": "v1"
              }
            ],
            "vanir_signatures_modified": "2026-10-20T14:14:34Z"
          }
        }
      ],
      "modified": "2026-10-20T14:14:34.447914353Z",
      "provider": "osv",
      "references": [
        "https://github.com/ValveSoftware/GameNetworkingSockets/commit/e0c86dcb9139771db3db0cfdb1fb8bef0af19c43",
        "https://research.checkpoint.com/2020/game-on-finding-vulnerabilities-in-valves-steam-sockets/"
      ],
      "provider_metadata": {}
    },
    "related_cves": [
      {
        "value": "CVE-2020-6017",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 388758,
  "published_at": "2020-12-03T14:15:11.02+00:00"
}