Security advisory

{
  "id": "f9d3c7ea99c6458d007e687cb23422b22cf84804f12dd02b46457debcd445edf",
  "url": "https://osv.dev/vulnerability/CVE-2021-35331",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "CVE-2021-35331",
    "summary": "In Tcl 8.6.11, a format string vulnerability in nmakehlp.c might allow code execution via a crafted file. NOTE: multiple third parties dispute the significance of this finding",
    "evidence": "osv:CVE-2021-35331",
    "products": [],
    "severity": "high",
    "structured": {
      "id": "CVE-2021-35331",
      "aliases": [
        "CVE-2021-35331"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/tcltk/tcl",
              "type": "GIT",
              "events": [
                {
                  "introduced": "17b5b3e0201cdf92d3c125776e1b2dd453f225bd"
                },
                {
                  "last_affected": "17b5b3e0201cdf92d3c125776e1b2dd453f225bd"
                },
                {
                  "fixed": "4705dbdde2f32ff90420765cd93e7ac71d81a222"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "cpe": "cpe:2.3:a:tcl:tcl:8.6.11:*:*:*:*:*:*:*",
                    "range": [
                      {
                        "introduced": "8.6.11"
                      },
                      {
                        "last_affected": "8.6.11"
                      }
                    ],
                    "source": "CPE_STRING"
                  },
                  {
                    "range": [
                      {
                        "fixed": "4705dbdde2f32ff90420765cd93e7ac71d81a222"
                      }
                    ],
                    "source": "REFERENCES_COMMIT"
                  }
                ]
              }
            }
          ],
          "versions": [
            "8.6.11",
            "core-8-6-11"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2021-35331.json",
            "vanir_signatures": [
              {
                "id": "CVE-2021-35331-03722e49",
                "digest": {
                  "threshold": 0.9,
                  "line_hashes": [
                    "338794718477778830788026938893809680996",
                    "167523017892673006030716419150005314888",
                    "255738228804160061589439085284092356741",
                    "128920200318728874743013425295381636087",
                    "76778023355815920090853215777728435607",
                    "105858589626416364655426904205864977080",
                    "172666521847550365368341013690159064849",
                    "307508334135556441185366936693295759738"
                  ]
                },
                "source": "https://github.com/tcltk/tcl/commit/4705dbdde2f32ff90420765cd93e7ac71d81a222",
                "target": {
                  "file": "win/nmakehlp.c"
                },
                "deprecated": false,
                "signature_type": "Line",
                "signature_version": "v1"
              },
              {
                "id": "CVE-2021-35331-73057c0f",
                "digest": {
                  "length": 1577,
                  "function_hash": "79655282905794098102193868097258390460"
                },
                "source": "https://github.com/tcltk/tcl/commit/4705dbdde2f32ff90420765cd93e7ac71d81a222",
                "target": {
                  "file": "win/nmakehlp.c",
                  "function": "SubstituteFile"
                },
                "deprecated": false,
                "signature_type": "Function",
                "signature_version": "v1"
              }
            ],
            "vanir_signatures_modified": "2026-10-20T14:28:26Z"
          }
        }
      ],
      "modified": "2026-10-20T14:28:26.447466717Z",
      "provider": "osv",
      "references": [
        "https://core.tcl-lang.org/tcl/info/28ef6c0c741408a2",
        "https://github.com/tcltk/tcl/commit/4705dbdde2f32ff90420765cd93e7ac71d81a222",
        "https://core.tcl-lang.org/tcl/info/bad6cc213dfe8280",
        "https://sqlite.org/forum/info/7dcd751996c93ec9"
      ],
      "provider_metadata": {}
    },
    "related_cves": [
      {
        "value": "CVE-2021-35331",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 389063,
  "published_at": "2021-07-05T15:15:07.997+00:00"
}