FKIE_CVE-2026-10645

Vulnerability from fkie_nvd - Published: 2026-06-23 01:16 - Updated: 2026-06-23 15:11
Severity
4.9 (Medium) - CVSS:3.1/AV:P/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:H
Summary
Zephyr's ext2 directory-entry parser does not fully validate on-disk directory entry structure before copying the entry name and advancing traversal state. In ext2_fetch_direntry() (subsys/fs/ext2/ext2_diskops.c), the code only checks de_name_len <= EXT2_MAX_FILE_NAME and then copies the name with memcpy without validating the structural relationship between de_rec_len, de_name_len, and the directory block boundary (for example that de_rec_len is non-zero, at least the size of the entry header, and that the record fits within the block). Callers such as find_dir_entry() and ext2_get_direntry() (subsys/fs/ext2/ext2_impl.c) then advance traversal using the unvalidated de_rec_len. A crafted ext2 image can therefore cause an out-of-bounds read from the directory block buffer when a malformed entry near the end of a block triggers an oversized name copy, or a zero-progress infinite loop when de_rec_len == 0. The issue is not reached at mount time but later through directory traversal paths such as pathname lookup, stat/open/unlink/rename, and readdir. The primary impact is denial of service and out-of-bounds reads under attacker-controlled ext2 images mounted from untrusted media.
References
vulnerabilities@zephyrproject.orghttps://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-hwrh-9h3x-vccm
Impacted products
Vendor Product Version
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "packageName": "Zephyr",
          "product": "Zephyr",
          "repo": "https://github.com/zephyrproject-rtos/zephyr",
          "vendor": "zephyrproject-rtos",
          "versions": [
            {
              "lessThanOrEqual": "4.4",
              "status": "affected",
              "version": "*",
              "versionType": "git"
            }
          ]
        }
      ],
      "source": "vulnerabilities@zephyrproject.org"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Zephyr\u0027s ext2 directory-entry parser does not fully validate on-disk directory entry structure before copying the entry name and advancing traversal state. In ext2_fetch_direntry() (subsys/fs/ext2/ext2_diskops.c), the code only checks de_name_len \u003c= EXT2_MAX_FILE_NAME and then copies the name with memcpy without validating the structural relationship between de_rec_len, de_name_len, and the directory block boundary (for example that de_rec_len is non-zero, at least the size of the entry header, and that the record fits within the block). Callers such as find_dir_entry() and ext2_get_direntry() (subsys/fs/ext2/ext2_impl.c) then advance traversal using the unvalidated de_rec_len. A crafted ext2 image can therefore cause an out-of-bounds read from the directory block buffer when a malformed entry near the end of a block triggers an oversized name copy, or a zero-progress infinite loop when de_rec_len == 0. The issue is not reached at mount time but later through directory traversal paths such as pathname lookup, stat/open/unlink/rename, and readdir. The primary impact is denial of service and out-of-bounds reads under attacker-controlled ext2 images mounted from untrusted media."
    }
  ],
  "id": "CVE-2026-10645",
  "lastModified": "2026-06-23T15:11:24.183",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "PHYSICAL",
          "availabilityImpact": "HIGH",
          "baseScore": 4.9,
          "baseSeverity": "MEDIUM",
          "confidentialityImpact": "LOW",
          "integrityImpact": "NONE",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "REQUIRED",
          "vectorString": "CVSS:3.1/AV:P/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 0.7,
        "impactScore": 4.2,
        "source": "vulnerabilities@zephyrproject.org",
        "type": "Secondary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-10645",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2026-06-23T12:18:26.712409Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2026-06-23T01:16:26.607",
  "references": [
    {
      "source": "vulnerabilities@zephyrproject.org",
      "url": "https://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-hwrh-9h3x-vccm"
    }
  ],
  "sourceIdentifier": "vulnerabilities@zephyrproject.org",
  "vulnStatus": "Awaiting Analysis",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-125"
        }
      ],
      "source": "vulnerabilities@zephyrproject.org",
      "type": "Secondary"
    }
  ]
}


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