{
  "schemaVersion": 1,
  "attribution": [
    {
      "source": "CISA Known Exploited Vulnerabilities",
      "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog",
      "licence": "US government work"
    },
    {
      "source": "GitHub Advisory Database",
      "url": "https://github.com/advisories",
      "licence": "CC BY 4.0"
    },
    {
      "source": "Have I Been Pwned",
      "url": "https://haveibeenpwned.com/",
      "licence": "CC BY 4.0"
    },
    {
      "source": "CVE Program (CVE records)",
      "url": "https://www.cve.org/Legal/TermsOfUse",
      "licence": "CVE Terms of Use",
      "notice": "Copyright © 1999-2026, The MITRE Corporation. CVE is a trademark and the CVE logo is a registered trademark of The MITRE Corporation.",
      "terms": "CVE Usage: MITRE hereby grants you a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable copyright license to reproduce, prepare derivative works of, publicly display, publicly perform, sublicense, and distribute Common Vulnerabilities and Exposures (CVE™). Any copy you make for such purposes is authorized provided that you reproduce MITRE's copyright designation and this license in any such copy."
    },
    {
      "source": "FIRST EPSS",
      "url": "https://www.first.org/epss/",
      "licence": "free to use; FIRST requests attribution"
    }
  ],
  "record": {
    "id": "CVE-2023-20135",
    "sourceURL": "https://www.cve.org/CVERecord?id=CVE-2023-20135",
    "idYear": 2023,
    "status": "PUBLISHED",
    "publishedAt": "2023-09-13T16:38:36.593Z",
    "updatedAt": "2025-12-16T18:23:19.364Z",
    "importedAt": "2026-10-24T01:56:49.724Z",
    "snapshot": {
      "id": "cve_2026-10-24_midnight_baseline",
      "at": "2026-10-24T00:00:00.000Z",
      "source": "https://github.com/CVEProject/cvelistV5/releases/tag/cve_2026-10-24_0100Z"
    },
    "facts": {
      "title": null,
      "summary": "A vulnerability in Cisco IOS XR Software image verification checks could allow an authenticated, local attacker to execute arbitrary code on the underlying operating system.\r\n\r This vulnerability is due to a time-of-check, time-of-use (TOCTOU) race condition when an install query regarding an ISO image is performed during an install operation that uses an ISO image. An attacker could exploit this vulnerability by modifying an ISO image and then carrying out install requests in parallel. A successful exploit could allow the attacker to execute arbitrary code on an affected device.",
      "affected": [
        {
          "vendor": "Cisco",
          "product": "Cisco IOS XR Software",
          "versions": [
            {
              "version": "7.5.3",
              "status": "affected"
            },
            {
              "version": "7.5.2",
              "status": "affected"
            },
            {
              "version": "7.5.4",
              "status": "affected"
            },
            {
              "version": "7.7.1",
              "status": "affected"
            },
            {
              "version": "7.7.2",
              "status": "affected"
            },
            {
              "version": "7.7.21",
              "status": "affected"
            },
            {
              "version": "7.8.1",
              "status": "affected"
            },
            {
              "version": "7.8.2",
              "status": "affected"
            },
            {
              "version": "7.9.1",
              "status": "affected"
            },
            {
              "version": "7.9.2",
              "status": "affected"
            }
          ]
        }
      ]
    }
  }
}