Vulnerability-Lookup

GHSA-4G74-7CFF-XCV8

Vulnerability from github – Published: 2025-11-05 18:44 – Updated: 2025-11-15 02:25

Summary

youki container escape via "masked path" abuse due to mount race conditions

Details

Impact

youki utilizes bind mounting the container's /dev/null as a file mask. When performing this operation, the initial validation of the source /dev/null was insufficient. Specifically, we initially failed to verify whether /dev/null was genuinely present. However, we did perform validation to ensure that the /dev/null path existed within the container, including checking for symbolic links. Additionally, there was a vulnerability in the timing between validation and the actual mount operation.

As a result, by replacing /dev/null with a symbolic link, we can bind-mount arbitrary files from the host system.

This is a different project, but the core logic is similar to the CVE in runc. Issues were identified in runc, and verification was also conducted in youki to confirm the problems. https://github.com/opencontainers/runc/security/advisories/GHSA-9493-h29p-rfm2

Credits

Thanks to Lei Wang (@ssst0n3 from Huawei) for finding and reporting the original runc's vulnerability (Attack 1), and Li Fubang (@lifubang from acmcoder.com, CIIC) for discovering another attack vector in runc (Attack 2) based on @ssst0n3's initial findings.

Also, @cyphar helped youki in finding the problem.

Severity

10.0 (Critical)


                  
                    CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H

7.3 (High)


                  
                    CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:A/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H

Show details on source website

JSON

To clipboard

{
  "affected": [
    {
      "package": {
        "ecosystem": "crates.io",
        "name": "youki"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "0.5.7"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2025-62161"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-363",
      "CWE-61"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2025-11-05T18:44:18Z",
    "nvd_published_at": "2025-11-06T00:15:36Z",
    "severity": "HIGH"
  },
  "details": "### Impact ###\n\nyouki utilizes bind mounting the container\u0027s `/dev/null` as a file mask. When performing this operation, the initial validation of the source `/dev/null` was insufficient. Specifically, we initially failed to verify whether `/dev/null` was genuinely present. However, we did perform validation to ensure that the `/dev/null` path existed within the container, including checking for symbolic links. Additionally, there was a vulnerability in the timing between validation and the actual mount operation.\n\nAs a result, by replacing `/dev/null` with a symbolic link, we can bind-mount arbitrary files from the host system.\n\nThis is a different project, but the core logic is similar to the CVE in runc. Issues were identified in runc, and verification was also conducted in youki to confirm the problems.\nhttps://github.com/opencontainers/runc/security/advisories/GHSA-9493-h29p-rfm2\n\n### Credits\n\nThanks to Lei Wang (@ssst0n3 from Huawei) for finding and reporting the original runc\u0027s vulnerability (Attack 1), and Li Fubang (@lifubang from acmcoder.com, CIIC) for discovering another attack vector in runc (Attack 2) based on @ssst0n3\u0027s initial findings.\n\nAlso, @cyphar helped youki in finding the problem.",
  "id": "GHSA-4g74-7cff-xcv8",
  "modified": "2025-11-15T02:25:02Z",
  "published": "2025-11-05T18:44:18Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/opencontainers/runc/security/advisories/GHSA-9493-h29p-rfm2"
    },
    {
      "type": "WEB",
      "url": "https://github.com/youki-dev/youki/security/advisories/GHSA-4g74-7cff-xcv8"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2025-62161"
    },
    {
      "type": "WEB",
      "url": "https://github.com/youki-dev/youki/commit/5886c91073b9be748bd8d5aed49c4a820548030a"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/youki-dev/youki"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H",
      "type": "CVSS_V3"
    },
    {
      "score": "CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:A/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H",
      "type": "CVSS_V4"
    }
  ],
  "summary": "youki container escape via \"masked path\" abuse due to mount race conditions"
}

CVE-2025-62161 (GCVE-0-2025-62161)

Vulnerability from cvelistv5 – Published: 2025-11-05 23:09 – Updated: 2025-11-06 21:20

Title

youki container escape via "masked path" abuse due to mount race conditions

Summary

Youki is a container runtime written in Rust. In versions 0.5.6 and below, the initial validation of the source /dev/null is insufficient, allowing container escape when youki utilizes bind mounting the container's /dev/null as a file mask. This issue is fixed in version 0.5.7.

Severity

7.3 (High)


                        
                          CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:A/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2025-11-06 21:20 UTC

CWE

CWE-363 - Race Condition Enabling Link Following
CWE-61 - UNIX Symbolic Link (Symlink) Following

Assigner

GitHub_M mitre root

References

2 references

URL	Tags
https://github.com/youki-dev/youki/security/advis…	x_refsource_CONFIRM
https://github.com/youki-dev/youki/commit/5886c91…	x_refsource_MISC

Impacted products

1 product

Vendor	Product	Version
youki-dev	youki	Affected: < 0.5.7

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2025-62161",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2025-11-06T21:20:10.358215Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2025-11-06T21:20:19.865Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "product": "youki",
          "vendor": "youki-dev",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 0.5.7"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "Youki is a container runtime written in Rust. In versions 0.5.6 and below, the initial validation of the source /dev/null is insufficient, allowing container escape when youki utilizes bind mounting the container\u0027s /dev/null as a file mask. This issue is fixed in version 0.5.7."
        }
      ],
      "metrics": [
        {
          "cvssV4_0": {
            "attackComplexity": "LOW",
            "attackRequirements": "PRESENT",
            "attackVector": "LOCAL",
            "baseScore": 7.3,
            "baseSeverity": "HIGH",
            "privilegesRequired": "LOW",
            "subAvailabilityImpact": "HIGH",
            "subConfidentialityImpact": "HIGH",
            "subIntegrityImpact": "HIGH",
            "userInteraction": "ACTIVE",
            "vectorString": "CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:A/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H",
            "version": "4.0",
            "vulnAvailabilityImpact": "HIGH",
            "vulnConfidentialityImpact": "HIGH",
            "vulnIntegrityImpact": "HIGH"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-363",
              "description": "CWE-363: Race Condition Enabling Link Following",
              "lang": "en",
              "type": "CWE"
            }
          ]
        },
        {
          "descriptions": [
            {
              "cweId": "CWE-61",
              "description": "CWE-61: UNIX Symbolic Link (Symlink) Following",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2025-11-05T23:09:09.014Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
      },
      "references": [
        {
          "name": "https://github.com/youki-dev/youki/security/advisories/GHSA-4g74-7cff-xcv8",
          "tags": [
            "x_refsource_CONFIRM"
          ],
          "url": "https://github.com/youki-dev/youki/security/advisories/GHSA-4g74-7cff-xcv8"
        },
        {
          "name": "https://github.com/youki-dev/youki/security/advisories/GHSA-4g74-7cff-xcv8",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/youki-dev/youki/security/advisories/GHSA-4g74-7cff-xcv8"
        },
        {
          "name": "https://github.com/youki-dev/youki/commit/5886c91073b9be748bd8d5aed49c4a820548030a",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/youki-dev/youki/commit/5886c91073b9be748bd8d5aed49c4a820548030a"
        }
      ],
      "source": {
        "advisory": "GHSA-4g74-7cff-xcv8",
        "discovery": "UNKNOWN"
      },
      "title": "youki container escape via \"masked path\" abuse due to mount race conditions"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
    "assignerShortName": "GitHub_M",
    "cveId": "CVE-2025-62161",
    "datePublished": "2025-11-05T23:09:09.014Z",
    "dateReserved": "2025-10-07T16:12:03.424Z",
    "dateUpdated": "2025-11-06T21:20:19.865Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

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.

Detection rules are retrieved from Rulezet.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.

Related by attack behaviour

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