CVE-2025-62596: Youki Denial of Service Vulnerability

HIGH
Advisory Identifier: GHSA-vf95-55w6-qmrf
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CVSS 10.0
CWE-363 CWE-61
Published
Advisory Summary

CVE-2025-62596 is a HIGH (CVSS 10.0) denial of service vulnerability (CWE-363: Race Condition Enabling Link Following) affecting Youki libraries in the crates.io ecosystem. The issue involves youki container escape and denial of service due to arbitrary write gadgets and procfs write redirects. Remediation is available by upgrading affected packages to version 0.5.7.

CVE-2025-62596 at a Glance

CVE Identifier CVE-2025-62596
GHSA Identifier GHSA-vf95-55w6-qmrf
Severity HIGH
CVSS v3.1 Base Score 10.0
CWE Classification CWE-363: Race Condition Enabling Link Following
Affected Product Youki
Package Ecosystem crates.io
Published Date
Last Updated

Security Impact

CVSS: 10.0

The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:H/A:H).

Attack Vector Network (AV:N)
Attack Complexity Low (AC:L)
Privileges Required None (PR:N)
User Interaction None (UI:N)
Scope Changed (S:C)
Confidentiality None (C:N)
Integrity High (I:H)
Availability High (A:H)

How to Fix CVE-2025-62596

To remediate this vulnerability, upgrade all affected Youki dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.

youki fixed: 0.5.7 
Upgrade youki to 0.5.7
Verify Direct and Transitive Dependencies

Run the following command in your project directory to verify that all resolved dependencies use the patched release: 

inspect dependencies for youki

How to Check if You Are Affected

To determine whether your application is affected by CVE-2025-62596, inspect your project dependencies for Youki:

inspect dependencies for youki

Analyze the terminal output to locate any version of Youki in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 0.5.7), your application is affected.

Note: Verify declared build manifests and deployed runtime container environments.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-363: Race Condition Enabling Link Following, where the product checks the status of a file or directory before accessing it, which produces a race condition in which the file can be replaced with a link before the access is performed, causing the product to access the wrong file. In Youki, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.

Source Advisory Statement

### 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.

CVE-2025-62596 Affected Youki Versions

1 component(s)
Fixed Versions:
0.5.7
Product / Package Ecosystem Affected Versions Fixed Version
youki
 crates.io
< 0.5.7
0.5.7

References

GitHub Advisory / Wiki ADVISORY
https://github.com/opencontainers/runc/security/advisories/GHSA-cgrx-mc8f-2prm
GitHub Advisory / Wiki ADVISORY
https://github.com/youki-dev/youki/security/advisories/GHSA-vf95-55w6-qmrf
NVD — CVE-2025-62596 NVD
https://nvd.nist.gov/vuln/detail/CVE-2025-62596
Security Fix Commit FIX COMMIT
https://github.com/youki-dev/youki/commit/5886c91073b9be748bd8d5aed49c4a820548030a
Youki Source Repository REPOSITORY
https://github.com/youki-dev/youki
pkg.go.dev/github.com/cyphar/f... WEB
https://pkg.go.dev/github.com/cyphar/filepath-securejoin/pathrs-lite/procfs
youtu.be/tgsejw_ubb8 WEB
https://youtu.be/tGseJW_uBB8
youtu.be/y1pabzxwrwq WEB
https://youtu.be/y1PaBzxwRWQ

Frequently Asked Questions

What is CVE-2025-62596?
CVE-2025-62596 is a security vulnerability in Youki involving youki container escape and denial of service due to arbitrary write gadgets and procfs write redirects under CWE-363: Race Condition Enabling Link Following.
Which Youki versions are affected?
Affected versions include releases prior to 0.5.7 across affected packages: youki.
What version fixes CVE-2025-62596?
Upgrading to 0.5.7 (or the latest patched release for your respective branch) resolves the vulnerability.
Is youki affected?
Yes, youki is affected in releases prior to 0.5.7. Upgrade your dependency to 0.5.7 or later.
What is the CVSS score of CVE-2025-62596?
CVE-2025-62596 has a CVSS v3.1 base score of 10.0 (HIGH) with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:H/A:H.
What CWE is associated with CVE-2025-62596?
CVE-2025-62596 is classified under CWE-363: Race Condition Enabling Link Following (The product checks the status of a file or directory before accessing it, which produces a race condition in which the file can be replaced with a link before the access is performed, causing the product to access the wrong file.).
How can I check crates.io dependencies for CVE-2025-62596?
Run the dependency tree command: 'inspect dependencies for youki'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.
Machine-readable OSV JSON OSV v1.5 Schema
Normalized schema output
View Raw JSON 
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-vf95-55w6-qmrf",
  "modified" : "2025-11-15T02:25:28Z",
  "published" : "2025-11-05T18:45:18Z",
  "aliases" : [ "CVE-2025-62596" ],
  "summary" : "youki container escape and denial of service due to arbitrary write gadgets and procfs write redirects",
  "details" : "### Impact ###\n\nyouki’s apparmor handling performs insufficiently strict write-target validation, which—combined with path substitution during pathname resolution—can 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 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" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:H/A:H"
  }, {
    "type" : "CVSS_V4",
    "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"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "crates.io",
      "name" : "youki"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "0.5.7"
      } ]
    } ]
  } ],
  "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"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-363", "CWE-61" ],
    "severity" : "HIGH",
    "github_reviewed" : true,
    "github_reviewed_at" : "2025-11-05T18:45:18Z",
    "nvd_published_at" : "2025-11-06T00:15:37Z"
  }
}