CVE-2026-97035 (GCVE-0-2026-97035)

Vulnerability from cvelistv5 – Published: 2026-11-11 03:13 – Updated: 2026-11-11 03:13
VLAI
Title
Unexpected code execution and arbitrary file write via Clang -gen-* and GCC -gnat* flags in cgo in cmd/go
Summary
When using Clang or GCC, building a malicious package that uses cgo could cause unexpected code execution at build time or write files to arbitrary directories via "-gen-*" or "-gnat*" flags in "#cgo" directives. The "-g*" wildcard in the compiler and linker flag allowlists previously matched Clang's two-argument "-gen-cdb-fragment-path <dir>" flag and GCC's two-argument "-gnatO <file>" flag, permitting compilation database fragments and sidecar output files to be written to arbitrary directories and desynchronizing flag argument parsing between the go command and the compiler driver so that subsequent arguments could be passed as unvalidated positional inputs to the linker. "-gen-*" and "-gnat*" flags are now disallowed in "#cgo" compiler and linker flags.
Severity
No CVSS data available.
CWE
  • CWE-88 - Improper Neutralization of Argument Delimiters in a Command ('Argument Injection')
Assigner
Go CNA under the Google root
CNA scorecard E 42/100 over 76 records in the last 180 days details
Impacted products
Vendor Product Version CPE status
Go toolchain cmd/go Affected: 0 , < 1.26.11 (semver)
Affected: 1.27.0-0 , < 1.27.4 (semver)
guessed Create a notification for this product.
Show details on NVD website

{
  "containers": {
    "cna": {
      "affected": [
        {
          "collectionURL": "https://pkg.go.dev",
          "defaultStatus": "unaffected",
          "packageName": "cmd/go",
          "product": "cmd/go",
          "vendor": "Go toolchain",
          "versions": [
            {
              "lessThan": "1.26.11",
              "status": "affected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThan": "1.27.4",
              "status": "affected",
              "version": "1.27.0-0",
              "versionType": "semver"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "When using Clang or GCC, building a malicious package that uses cgo could cause unexpected code execution at build time or write files to arbitrary directories via \"-gen-*\" or \"-gnat*\" flags in \"#cgo\" directives. The \"-g*\" wildcard in the compiler and linker flag allowlists previously matched Clang\u0027s two-argument \"-gen-cdb-fragment-path \u003cdir\u003e\" flag and GCC\u0027s two-argument \"-gnatO \u003cfile\u003e\" flag, permitting compilation database fragments and sidecar output files to be written to arbitrary directories and desynchronizing flag argument parsing between the go command and the compiler driver so that subsequent arguments could be passed as unvalidated positional inputs to the linker. \"-gen-*\" and \"-gnat*\" flags are now disallowed in \"#cgo\" compiler and linker flags."
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "description": "CWE-88: Improper Neutralization of Argument Delimiters in a Command (\u0027Argument Injection\u0027)",
              "lang": "en"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-11-11T03:13:16.798Z",
        "orgId": "1bb62c36-49e3-4200-9d77-64a1400537cc",
        "shortName": "Go"
      },
      "references": [
        {
          "url": "https://go.dev/cl/862148"
        },
        {
          "url": "https://go.dev/issue/82575"
        },
        {
          "url": "https://groups.google.com/g/golang-announce/c/iY8TY0wWgbM"
        },
        {
          "url": "https://pkg.go.dev/vuln/GO-2026-6856"
        }
      ],
      "title": "Unexpected code execution and arbitrary file write via Clang -gen-* and GCC -gnat* flags in cgo in cmd/go"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "1bb62c36-49e3-4200-9d77-64a1400537cc",
    "assignerShortName": "Go",
    "cveId": "CVE-2026-97035",
    "datePublished": "2026-11-11T03:13:16.798Z",
    "dateReserved": "2026-09-23T23:05:04.987Z",
    "dateUpdated": "2026-11-11T03:13:16.798Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "nvd": {
      "cve": {
        "affected": [
          {
            "affectedData": [
              {
                "collectionURL": "https://pkg.go.dev",
                "defaultStatus": "unaffected",
                "packageName": "cmd/go",
                "product": "cmd/go",
                "vendor": "Go toolchain",
                "versions": [
                  {
                    "lessThan": "1.26.11",
                    "status": "affected",
                    "version": "0",
                    "versionType": "semver"
                  },
                  {
                    "lessThan": "1.27.4",
                    "status": "affected",
                    "version": "1.27.0-0",
                    "versionType": "semver"
                  }
                ]
              }
            ],
            "source": "security@golang.org"
          }
        ],
        "cveTags": [],
        "descriptions": [
          {
            "lang": "en",
            "value": "When using Clang or GCC, building a malicious package that uses cgo could cause unexpected code execution at build time or write files to arbitrary directories via \"-gen-*\" or \"-gnat*\" flags in \"#cgo\" directives. The \"-g*\" wildcard in the compiler and linker flag allowlists previously matched Clang\u0027s two-argument \"-gen-cdb-fragment-path \u003cdir\u003e\" flag and GCC\u0027s two-argument \"-gnatO \u003cfile\u003e\" flag, permitting compilation database fragments and sidecar output files to be written to arbitrary directories and desynchronizing flag argument parsing between the go command and the compiler driver so that subsequent arguments could be passed as unvalidated positional inputs to the linker. \"-gen-*\" and \"-gnat*\" flags are now disallowed in \"#cgo\" compiler and linker flags."
          }
        ],
        "id": "CVE-2026-97035",
        "lastModified": "2026-11-11T05:19:57.550",
        "metrics": {},
        "published": "2026-11-11T05:19:57.550",
        "references": [
          {
            "source": "security@golang.org",
            "url": "https://go.dev/cl/862148"
          },
          {
            "source": "security@golang.org",
            "url": "https://go.dev/issue/82575"
          },
          {
            "source": "security@golang.org",
            "url": "https://groups.google.com/g/golang-announce/c/iY8TY0wWgbM"
          },
          {
            "source": "security@golang.org",
            "url": "https://pkg.go.dev/vuln/GO-2026-6856"
          }
        ],
        "sourceIdentifier": "security@golang.org",
        "vulnStatus": "Received"
      }
    }
  }
}



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