CVE-2026-82018 (GCVE-0-2026-82018)

Vulnerability from cvelistv5 – Published: 2026-08-28 21:11 – Updated: 2026-09-02 18:46
VLAI
Title
IGEL OS 12 / 11 Secure Boot Bypass via Unsigned igel.conf File
Summary
IGEL OS 12 before 12.9.0, 12.8.3 LTS and IGEL OS 11 before 11.11.150 contain a secure boot bypass vulnerability in the GRUB boot stage that allows physically present attackers to gain unauthorized root access by placing an unsigned empty file named igel.conf on a partition. Attackers can exploit GRUB's fail-open signature verification behavior to drop into an interactive GRUB prompt, then boot the device's own kernel with additional command-line arguments to obtain a root shell with the disk unlocked while leaving TPM PCR values unaltered.
Severity
6.8 (Medium)
CVSS:4.0/AV:P/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N
6.1 (Medium)
CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
SSVC
Exploitation: none Automatable: no Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-02 18:46 UTC
CWE
  • CWE-636 - Not Failing Securely ('Failing Open')
Assigner
References
Impacted products
Vendor Product Version CPE status
IGEL IGEL OS 12 Affected: 12.0.0 , ≤ 12.8.2 (semver)
Unaffected: 12.8.3 (semver)
Unaffected: 12.9.0 (semver)
guessed Create a notification for this product.
IGEL IGEL OS 11 Affected: 11.0.0 , < 11.11.150 (semver)
guessed Create a notification for this product.
Date Public
2026-06-17 00:00
Credits
Darren McDonald from AmberWolf
Show details on NVD website
To clipboard 

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-82018",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "total"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-09-02T18:46:35.490048Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-09-02T18:46:41.967Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "defaultStatus": "affected",
          "product": "IGEL OS 12",
          "vendor": "IGEL",
          "versions": [
            {
              "lessThanOrEqual": "12.8.2",
              "status": "affected",
              "version": "12.0.0",
              "versionType": "semver"
            },
            {
              "status": "unaffected",
              "version": "12.8.3",
              "versionType": "semver"
            },
            {
              "status": "unaffected",
              "version": "12.9.0",
              "versionType": "semver"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "IGEL OS 11",
          "vendor": "IGEL",
          "versions": [
            {
              "lessThan": "11.11.150",
              "status": "affected",
              "version": "11.0.0",
              "versionType": "semver"
            }
          ]
        }
      ],
      "credits": [
        {
          "lang": "en",
          "type": "finder",
          "value": "Darren McDonald from AmberWolf"
        }
      ],
      "datePublic": "2026-06-17T00:00:00.000Z",
      "descriptions": [
        {
          "lang": "en",
          "value": "IGEL OS 12 before 12.9.0, 12.8.3 LTS and IGEL OS 11 before 11.11.150 contain a secure boot bypass vulnerability in the GRUB boot stage that allows physically present attackers to gain unauthorized root access by placing an unsigned empty file named igel.conf on a partition. Attackers can exploit GRUB\u0027s fail-open signature verification behavior to drop into an interactive GRUB prompt, then boot the device\u0027s own kernel with additional command-line arguments to obtain a root shell with the disk unlocked while leaving TPM PCR values unaltered."
        }
      ],
      "metrics": [
        {
          "cvssV4_0": {
            "Automatable": "NOT_DEFINED",
            "Recovery": "NOT_DEFINED",
            "Safety": "NOT_DEFINED",
            "attackComplexity": "LOW",
            "attackRequirements": "NONE",
            "attackVector": "PHYSICAL",
            "baseScore": 6.8,
            "baseSeverity": "MEDIUM",
            "exploitMaturity": "NOT_DEFINED",
            "privilegesRequired": "NONE",
            "providerUrgency": "NOT_DEFINED",
            "subAvailabilityImpact": "NONE",
            "subConfidentialityImpact": "NONE",
            "subIntegrityImpact": "NONE",
            "userInteraction": "NONE",
            "valueDensity": "NOT_DEFINED",
            "vectorString": "CVSS:4.0/AV:P/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N",
            "version": "4.0",
            "vulnAvailabilityImpact": "NONE",
            "vulnConfidentialityImpact": "HIGH",
            "vulnIntegrityImpact": "HIGH",
            "vulnerabilityResponseEffort": "NOT_DEFINED"
          },
          "format": "CVSS",
          "scenarios": [
            {
              "lang": "en",
              "value": "GENERAL"
            }
          ]
        },
        {
          "cvssV3_1": {
            "attackComplexity": "LOW",
            "attackVector": "PHYSICAL",
            "availabilityImpact": "NONE",
            "baseScore": 6.1,
            "baseSeverity": "MEDIUM",
            "confidentialityImpact": "HIGH",
            "integrityImpact": "HIGH",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N",
            "version": "3.1"
          },
          "format": "CVSS",
          "scenarios": [
            {
              "lang": "en",
              "value": "GENERAL"
            }
          ]
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-636",
              "description": "Not Failing Securely (\u0027Failing Open\u0027)",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-28T21:11:43.223Z",
        "orgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
        "shortName": "VulnCheck"
      },
      "references": [
        {
          "name": "Vendor Advisory",
          "tags": [
            "vendor-advisory",
            "patch"
          ],
          "url": "https://kb.igel.com/en/security-safety/current/isn-2026-20-grub-shell-escape-in-igel-os"
        },
        {
          "name": "AmberWolf Blog",
          "tags": [
            "technical-description"
          ],
          "url": "https://blog.amberwolf.com/blog/2026/august/thin-client-thin-crypto-overview/"
        },
        {
          "name": "DEF CON 34 Presentation",
          "url": "https://media.defcon.org/DEF%20CON%2034/DEF%20CON%2034%20presentations/DEF%20CON%2034%20presentations/DEF%20CON%2034%20-%20Darren%20McDonald%20-%20Thin%20Client%20Thin%20Crypto%20-%20Bypassing%20Full-Desk%20Encryption%20Across%20Three%20Major%20Thin%20Clients%20Vendors%20without%20Breaking%20a%20Ci.pdf"
        },
        {
          "tags": [
            "third-party-advisory"
          ],
          "url": "https://www.vulncheck.com/advisories/igel-os-12-11-secure-boot-bypass-via-unsigned-igel-conf-file"
        }
      ],
      "source": {
        "discovery": "EXTERNAL"
      },
      "title": "IGEL OS 12 / 11 Secure Boot Bypass via Unsigned igel.conf File",
      "x_generator": {
        "engine": "vulncheck"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
    "assignerShortName": "VulnCheck",
    "cveId": "CVE-2026-82018",
    "datePublished": "2026-08-28T21:11:24.911Z",
    "dateReserved": "2026-08-27T21:39:20.459Z",
    "dateUpdated": "2026-09-02T18:46:41.967Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2026-82018",
      "date": "2026-09-29",
      "epss": "0.00251",
      "percentile": "0.14799"
    },
    "nvd": {
      "cve": {
        "affected": [
          {
            "affectedData": [
              {
                "defaultStatus": "affected",
                "product": "IGEL OS 12",
                "vendor": "IGEL",
                "versions": [
                  {
                    "lessThanOrEqual": "12.8.2",
                    "status": "affected",
                    "version": "12.0.0",
                    "versionType": "semver"
                  },
                  {
                    "status": "unaffected",
                    "version": "12.8.3",
                    "versionType": "semver"
                  },
                  {
                    "status": "unaffected",
                    "version": "12.9.0",
                    "versionType": "semver"
                  }
                ]
              },
              {
                "defaultStatus": "affected",
                "product": "IGEL OS 11",
                "vendor": "IGEL",
                "versions": [
                  {
                    "lessThan": "11.11.150",
                    "status": "affected",
                    "version": "11.0.0",
                    "versionType": "semver"
                  }
                ]
              }
            ],
            "source": "disclosure@vulncheck.com"
          }
        ],
        "cveTags": [],
        "descriptions": [
          {
            "lang": "en",
            "value": "IGEL OS 12 before 12.9.0, 12.8.3 LTS and IGEL OS 11 before 11.11.150 contain a secure boot bypass vulnerability in the GRUB boot stage that allows physically present attackers to gain unauthorized root access by placing an unsigned empty file named igel.conf on a partition. Attackers can exploit GRUB\u0027s fail-open signature verification behavior to drop into an interactive GRUB prompt, then boot the device\u0027s own kernel with additional command-line arguments to obtain a root shell with the disk unlocked while leaving TPM PCR values unaltered."
          }
        ],
        "id": "CVE-2026-82018",
        "lastModified": "2026-09-24T20:44:42.207",
        "metrics": {
          "cvssMetricV31": [
            {
              "cvssData": {
                "attackComplexity": "LOW",
                "attackVector": "PHYSICAL",
                "availabilityImpact": "NONE",
                "baseScore": 6.1,
                "baseSeverity": "MEDIUM",
                "confidentialityImpact": "HIGH",
                "integrityImpact": "HIGH",
                "privilegesRequired": "NONE",
                "scope": "UNCHANGED",
                "userInteraction": "NONE",
                "vectorString": "CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N",
                "version": "3.1"
              },
              "exploitabilityScore": 0.9,
              "impactScore": 5.2,
              "source": "disclosure@vulncheck.com",
              "type": "Secondary"
            }
          ],
          "cvssMetricV40": [
            {
              "cvssData": {
                "Automatable": "NOT_DEFINED",
                "Recovery": "NOT_DEFINED",
                "Safety": "NOT_DEFINED",
                "attackComplexity": "LOW",
                "attackRequirements": "NONE",
                "attackVector": "PHYSICAL",
                "availabilityRequirement": "NOT_DEFINED",
                "baseScore": 6.8,
                "baseSeverity": "MEDIUM",
                "confidentialityRequirement": "NOT_DEFINED",
                "exploitMaturity": "NOT_DEFINED",
                "integrityRequirement": "NOT_DEFINED",
                "modifiedAttackComplexity": "NOT_DEFINED",
                "modifiedAttackRequirements": "NOT_DEFINED",
                "modifiedAttackVector": "NOT_DEFINED",
                "modifiedPrivilegesRequired": "NOT_DEFINED",
                "modifiedSubAvailabilityImpact": "NOT_DEFINED",
                "modifiedSubConfidentialityImpact": "NOT_DEFINED",
                "modifiedSubIntegrityImpact": "NOT_DEFINED",
                "modifiedUserInteraction": "NOT_DEFINED",
                "modifiedVulnAvailabilityImpact": "NOT_DEFINED",
                "modifiedVulnConfidentialityImpact": "NOT_DEFINED",
                "modifiedVulnIntegrityImpact": "NOT_DEFINED",
                "privilegesRequired": "NONE",
                "providerUrgency": "NOT_DEFINED",
                "subAvailabilityImpact": "NONE",
                "subConfidentialityImpact": "NONE",
                "subIntegrityImpact": "NONE",
                "userInteraction": "NONE",
                "valueDensity": "NOT_DEFINED",
                "vectorString": "CVSS:4.0/AV:P/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
                "version": "4.0",
                "vulnAvailabilityImpact": "NONE",
                "vulnConfidentialityImpact": "HIGH",
                "vulnIntegrityImpact": "HIGH",
                "vulnerabilityResponseEffort": "NOT_DEFINED"
              },
              "source": "disclosure@vulncheck.com",
              "type": "Secondary"
            }
          ],
          "ssvcV203": [
            {
              "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
              "ssvcData": {
                "id": "CVE-2026-82018",
                "options": [
                  {
                    "exploitation": "none"
                  },
                  {
                    "automatable": "no"
                  },
                  {
                    "technicalImpact": "total"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-09-02T18:46:35.490048Z",
                "version": "2.0.3"
              }
            }
          ]
        },
        "published": "2026-08-28T22:16:55.217",
        "references": [
          {
            "source": "disclosure@vulncheck.com",
            "url": "https://blog.amberwolf.com/blog/2026/august/thin-client-thin-crypto-overview/"
          },
          {
            "source": "disclosure@vulncheck.com",
            "url": "https://kb.igel.com/en/security-safety/current/isn-2026-20-grub-shell-escape-in-igel-os"
          },
          {
            "source": "disclosure@vulncheck.com",
            "url": "https://media.defcon.org/DEF%20CON%2034/DEF%20CON%2034%20presentations/DEF%20CON%2034%20presentations/DEF%20CON%2034%20-%20Darren%20McDonald%20-%20Thin%20Client%20Thin%20Crypto%20-%20Bypassing%20Full-Desk%20Encryption%20Across%20Three%20Major%20Thin%20Clients%20Vendors%20without%20Breaking%20a%20Ci.pdf"
          },
          {
            "source": "disclosure@vulncheck.com",
            "url": "https://www.vulncheck.com/advisories/igel-os-12-11-secure-boot-bypass-via-unsigned-igel-conf-file"
          }
        ],
        "sourceIdentifier": "disclosure@vulncheck.com",
        "vulnStatus": "Awaiting Analysis",
        "weaknesses": [
          {
            "description": [
              {
                "lang": "en",
                "value": "CWE-636"
              }
            ],
            "source": "disclosure@vulncheck.com",
            "type": "Secondary"
          }
        ]
      }
    }
  }
}



Log in or create an account to share your comment.




Tags
Taxonomy of the tags.





Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.