Vulnerability-Lookup

GHSA-VF95-55W6-QMRF

Vulnerability from github – Published: 2025-11-05 18:45 – Updated: 2025-11-15 02:25

Summary

youki container escape and denial of service due to arbitrary write gadgets and procfs write redirects

Details

Impact

youki’s apparmor handling performs insufficiently strict write-target validation, which—combined with path substitution during pathname resolution—can allow writes to unintended procfs locations.

Weak write-target check youki only verifies that the destination lies somewhere under procfs. As a result, a write intended for /proc/self/attr/apparmor/exec can succeed even if the path has been redirected to /proc/sys/kernel/hostname(which is also in procfs).

Path substitution While resolving a path component-by-component, a shared-mount race can substitute intermediate components and redirect the final target.

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-cgrx-mc8f-2prm

Credits

Thanks to Li Fubang (@lifubang from acmcoder.com, CIIC) and Tõnis Tiigi (@tonistiigi from Docker) for both independently discovering runc's original vulnerability, as well as Aleksa Sarai (@cyphar from SUSE) for the original research into this class of security issues and solutions.

Severity

10.0 (Critical)


                  
                    CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/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-2025-62596"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-363",
      "CWE-61"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2025-11-05T18:45:18Z",
    "nvd_published_at": "2025-11-06T00:15:37Z",
    "severity": "HIGH"
  },
  "details": "### Impact ###\n\nyouki\u2019s apparmor handling performs insufficiently strict write-target validation, which\u2014combined with path substitution during pathname resolution\u2014can allow writes to unintended procfs locations.\n\n**Weak write-target check**\nyouki only verifies that the destination lies somewhere under procfs. As a result, a write intended for `/proc/self/attr/apparmor/exec` can succeed even if the path has been redirected to `/proc/sys/kernel/hostname`(which is also in procfs).\n\n**Path substitution**\nWhile resolving a path component-by-component, a shared-mount race can substitute intermediate components and redirect the final target.\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-cgrx-mc8f-2prm\n\n### Credits ###\n\nThanks to Li Fubang (@lifubang from acmcoder.com, CIIC) and T\u00f5nis Tiigi (@tonistiigi from Docker) for both independently discovering runc\u0027s original vulnerability, as well as Aleksa Sarai (@cyphar from SUSE) for the original research into this class of security issues and solutions.",
  "id": "GHSA-vf95-55w6-qmrf",
  "modified": "2025-11-15T02:25:28Z",
  "published": "2025-11-05T18:45:18Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/opencontainers/runc/security/advisories/GHSA-cgrx-mc8f-2prm"
    },
    {
      "type": "WEB",
      "url": "https://github.com/youki-dev/youki/security/advisories/GHSA-vf95-55w6-qmrf"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2025-62596"
    },
    {
      "type": "WEB",
      "url": "https://github.com/youki-dev/youki/commit/5886c91073b9be748bd8d5aed49c4a820548030a"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/youki-dev/youki"
    },
    {
      "type": "WEB",
      "url": "https://pkg.go.dev/github.com/cyphar/filepath-securejoin/pathrs-lite/procfs"
    },
    {
      "type": "WEB",
      "url": "https://youtu.be/tGseJW_uBB8"
    },
    {
      "type": "WEB",
      "url": "https://youtu.be/y1PaBzxwRWQ"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/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 and denial of service due to arbitrary write gadgets and procfs write redirects"
}

CVE-2025-62596 (GCVE-0-2025-62596)

Vulnerability from cvelistv5 – Published: 2025-11-05 23:14 – Updated: 2025-11-06 16:54

Title

youki container escape and denial of service due to arbitrary write gadgets and procfs write redirects

Summary

Youki is a container runtime written in Rust. In versions 0.5.6 and below, youki’s apparmor handling performs insufficiently strict write-target validation, and when combined with path substitution during pathname resolution, can allow writes to unintended procfs locations. While resolving a path component-by-component, a shared-mount race can substitute intermediate components and redirect the final target. 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: total

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2025-11-06 16:54 UTC

CWE

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

Assigner

GitHub_M mitre root Scorecard

References

5 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
https://pkg.go.dev/github.com/cyphar/filepath-sec…	x_refsource_MISC
https://youtu.be/tGseJW_uBB8	x_refsource_MISC
https://youtu.be/y1PaBzxwRWQ	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-2025-62596",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "total"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2025-11-06T16:54:08.273724Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2025-11-06T16:54:15.942Z",
          "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, youki\u2019s apparmor handling performs insufficiently strict write-target validation, and when combined with path substitution during pathname resolution, can allow writes to unintended procfs locations. While resolving a path component-by-component, a shared-mount race can substitute intermediate components and redirect the final target. 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-61",
              "description": "CWE-61: UNIX Symbolic Link (Symlink) Following",
              "lang": "en",
              "type": "CWE"
            }
          ]
        },
        {
          "descriptions": [
            {
              "cweId": "CWE-363",
              "description": "CWE-363: Race Condition Enabling Link Following",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2025-11-05T23:14:37.167Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
      },
      "references": [
        {
          "name": "https://github.com/youki-dev/youki/security/advisories/GHSA-vf95-55w6-qmrf",
          "tags": [
            "x_refsource_CONFIRM"
          ],
          "url": "https://github.com/youki-dev/youki/security/advisories/GHSA-vf95-55w6-qmrf"
        },
        {
          "name": "https://github.com/youki-dev/youki/commit/5886c91073b9be748bd8d5aed49c4a820548030a",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/youki-dev/youki/commit/5886c91073b9be748bd8d5aed49c4a820548030a"
        },
        {
          "name": "https://pkg.go.dev/github.com/cyphar/filepath-securejoin/pathrs-lite/procfs",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://pkg.go.dev/github.com/cyphar/filepath-securejoin/pathrs-lite/procfs"
        },
        {
          "name": "https://youtu.be/tGseJW_uBB8",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://youtu.be/tGseJW_uBB8"
        },
        {
          "name": "https://youtu.be/y1PaBzxwRWQ",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://youtu.be/y1PaBzxwRWQ"
        }
      ],
      "source": {
        "advisory": "GHSA-vf95-55w6-qmrf",
        "discovery": "UNKNOWN"
      },
      "title": "youki container escape and denial of service due to arbitrary write gadgets and procfs write redirects"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
    "assignerShortName": "GitHub_M",
    "cveId": "CVE-2025-62596",
    "datePublished": "2025-11-05T23:14:37.167Z",
    "dateReserved": "2025-10-16T19:24:37.266Z",
    "dateUpdated": "2025-11-06T16:54:15.942Z",
    "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.

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

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.

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