verify-usb before 1.4.9 Symlink Directory Traversal Code Execution

{
  "id": "f4100e8a0c5299cf1b291bd7ad21df752645b7c5c5c045535016a33140e59c98",
  "url": "https://osv.dev/vulnerability/CVE-2026-81690",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "verify-usb before 1.4.9 Symlink Directory Traversal Code Execution",
    "summary": "openssl-encrypt (pip package) before 1.4.9 contains a symlink-following flaw in its verify-usb v2 added-file allowlist scan. The scan enumerated the drive with rglob(), which in CPython does not descend into symlinked directories and treats the symlink as an ordinary directory, while O_NOFOLLOW on the hash side binds only the final path component. An evil-maid attacker with physical access to the removable drive could replace a tool-tree directory with a symlink to a copy containing byte-identical files plus a planted __pycache__/*.pyc file (which CPython loads in preference to recompiling the clean .py). The planted file is never enumerated, added_files stays 0, and verify-usb reports PASSED, resulting in code execution when the victim runs the portable install. Fixed in 1.4.9 (affects both 1.4.x and 1.5.x lines).",
    "evidence": "osv:CVE-2026-81690",
    "products": [],
    "severity": "high",
    "structured": {
      "id": "CVE-2026-81690",
      "aliases": [
        "CVE-2026-81690",
        "GHSA-hw7h-wqf5-6crx",
        "PYSEC-2026-3796"
      ],
      "metrics": [
        {
          "type": "CVSS_V4",
          "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/jahlives/openssl_encrypt",
              "type": "GIT",
              "events": [
                {
                  "introduced": "0"
                },
                {
                  "fixed": "39b0a010cae90520f74b7194f61fedd43af04ef8"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "range": [
                      {
                        "introduced": "0"
                      },
                      {
                        "fixed": "1.4.9"
                      }
                    ],
                    "source": "AFFECTED_FIELD",
                    "strategy": "StandardRange"
                  },
                  {
                    "cpe": "cpe:2.3:a:jahlives:openssl_encrypt:*:*:*:*:*:python:*:*",
                    "range": [
                      {
                        "introduced": "0"
                      },
                      {
                        "fixed": "1.4.9"
                      }
                    ],
                    "source": "CPE_RANGE"
                  }
                ]
              }
            }
          ],
          "versions": [
            "v1.4.7",
            "v1.4.6",
            "v1.4.5",
            "v1.4.4",
            "v1.4.2",
            "v1.4.1rc2",
            "v1.4.1rc1",
            "v1.4.0"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-81690.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:49.443955094Z",
      "provider": "osv",
      "references": [
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/81xxx/CVE-2026-81690.json",
        "https://github.com/jahlives/openssl_encrypt/security/advisories/GHSA-hw7h-wqf5-6crx",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-81690",
        "https://www.vulncheck.com/advisories/verify-usb-before-1.4.9-symlink-directory-traversal-code-execution"
      ],
      "provider_metadata": {
        "cwe_ids": [
          "CWE-59"
        ],
        "cna_assigner": "VulnCheck",
        "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/81xxx/CVE-2026-81690.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-81690",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 517986,
  "published_at": "2026-08-27T14:50:55.418+00:00"
}