CVE-2026-35362: uucore Safe_traversal TOCTOU Protection Only Enabled Vulnerability

LOW
Advisory Identifier: GHSA-w6xc-g9qj-vp32
CVSS 3.6
CWE-367
Published
Advisory Summary

CVE-2026-35362 is a LOW (CVSS 3.6) safe_traversal toctou protection only enabled vulnerability (CWE-367: Time-of-check Time-of-use (TOCTOU) Race Condition) affecting uucore libraries in the crates.io ecosystem. The issue involves safe_traversal toctou protection only enabled on linux. Remediation is available by upgrading affected packages to version 0.6.0.

CVE-2026-35362 at a Glance

CVE Identifier CVE-2026-35362
GHSA Identifier GHSA-w6xc-g9qj-vp32
Severity LOW
CVSS v3.1 Base Score 3.6
CWE Classification CWE-367: Time-of-check Time-of-use (TOCTOU) Race Condition
Affected Product uucore
Package Ecosystem crates.io
Published Date
Last Updated

Security Impact

CVSS: 3.6

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

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

How to Fix CVE-2026-35362

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

uucore fixed: 0.6.0
Upgrade uucore to 0.6.0
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 uucore

How to Check if You Are Affected

To determine whether your application is affected by CVE-2026-35362, inspect your project dependencies for uucore:

inspect dependencies for uucore

Analyze the terminal output to locate any version of uucore in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 0.6.0), 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-367: Time-of-check Time-of-use (TOCTOU) Race Condition, where the product checks the state of a resource before using that resource, but the resource's state can change between the check and the use in a way that invalidates the results of the check. In uucore, 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

The safe_traversal module in uutils coreutils, which provides protection against Time-of-Check to Time-of-Use (TOCTOU) symlink races using file-descriptor-relative syscalls, is incorrectly limited to Linux targets. On other Unix-like systems such as macOS and FreeBSD, the utility fails to utilize these protections, leaving directory traversal operations vulnerable to symlink race conditions. --- _Zellic finding 3.59. Reported in the Zellic *uutils coreutils Program Security Assessment* (for Canonical, Jan 2026), audited commit `3a07ffc5a9bd4c283e75afa548ba1f1957bad242`._

CVE-2026-35362 Affected uucore Versions

1 component(s)
Fixed Versions:
0.6.0
Product / Package Ecosystem Affected Versions Fixed Version
uucore
crates.io
< 0.6.0
0.6.0

References

Frequently Asked Questions

What is CVE-2026-35362?
CVE-2026-35362 is a security vulnerability in uucore involving safe_traversal TOCTOU protection only enabled on Linux under CWE-367: Time-of-check Time-of-use (TOCTOU) Race Condition.
Which uucore versions are affected?
Affected versions include releases prior to 0.6.0 across affected packages: uucore.
What version fixes CVE-2026-35362?
Upgrading to 0.6.0 (or the latest patched release for your respective branch) resolves the vulnerability.
Is uucore affected?
Yes, uucore is affected in releases prior to 0.6.0. Upgrade your dependency to 0.6.0 or later.
What is the CVSS score of CVE-2026-35362?
CVE-2026-35362 has a CVSS v3.1 base score of 3.6 (LOW) with vector string CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:N.
What CWE is associated with CVE-2026-35362?
CVE-2026-35362 is classified under CWE-367: Time-of-check Time-of-use (TOCTOU) Race Condition (The product checks the state of a resource before using that resource, but the resource's state can change between the check and the use in a way that invalidates the results of the check.).
How can I check crates.io dependencies for CVE-2026-35362?
Run the dependency tree command: 'inspect dependencies for uucore'. 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
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-w6xc-g9qj-vp32",
  "modified" : "2026-07-06T20:25:15Z",
  "published" : "2026-07-06T20:25:15Z",
  "aliases" : [ "CVE-2026-35362" ],
  "summary" : "uucore: safe_traversal TOCTOU protection only enabled on Linux",
  "details" : "The safe_traversal module in uutils coreutils, which provides protection against Time-of-Check to Time-of-Use (TOCTOU) symlink races using file-descriptor-relative syscalls, is incorrectly limited to Linux targets. On other Unix-like systems such as macOS and FreeBSD, the utility fails to utilize these protections, leaving directory traversal operations vulnerable to symlink race conditions.\n\n---\n_Zellic finding 3.59. Reported in the Zellic *uutils coreutils Program Security Assessment* (for Canonical, Jan 2026), audited commit `3a07ffc5a9bd4c283e75afa548ba1f1957bad242`._",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "crates.io",
      "name" : "uucore"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "0.6.0"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/uutils/coreutils/security/advisories/GHSA-w6xc-g9qj-vp32"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-35362"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/uutils/coreutils/pull/9792"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/uutils/coreutils/commit/30239e69a328e76d2377f2a0bc02fbde61c34280"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/uutils/coreutils"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/uutils/coreutils/releases/tag/0.6.0"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-367" ],
    "severity" : "LOW",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-07-06T20:25:15Z",
    "nvd_published_at" : null
  }
}