CVE-2026-35356: install -D Symlink Race Vulnerability

MODERATE
Advisory Identifier: GHSA-gwm6-q8ch-hcfr
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CVSS 6.3
CWE-367 CWE-59
Published
Advisory Summary

CVE-2026-35356 is a MODERATE (CVSS 6.3) symlink race vulnerability (CWE-367: Time-of-check Time-of-use (TOCTOU) Race Condition) affecting install -D libraries in the crates.io ecosystem. The issue involves symlink race in directory creation allows arbitrary file overwrite. Remediation is available by upgrading affected packages to version 0.7.0.

CVE-2026-35356 at a Glance

CVE Identifier CVE-2026-35356
GHSA Identifier GHSA-gwm6-q8ch-hcfr
Severity MODERATE
CVSS v3.1 Base Score 6.3
CWE Classification CWE-367: Time-of-check Time-of-use (TOCTOU) Race Condition
Affected Product install -D
Package Ecosystem crates.io
Published Date
Last Updated

Security Impact

CVSS: 6.3

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:N/I:H/A:H).

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 None (C:N)
Integrity High (I:H)
Availability High (A:H)

How to Fix CVE-2026-35356

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

uu_install fixed: 0.7.0 
Upgrade uu_install to 0.7.0
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 uu_install

How to Check if You Are Affected

To determine whether your application is affected by CVE-2026-35356, inspect your project dependencies for install -D:

inspect dependencies for uu_install

Analyze the terminal output to locate any version of install -D in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 0.7.0), 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 install -D, 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 `-D` path runs `fs::create_dir_all` on a pathname then later opens the destination via path-based `File::create`/`fs::copy`, neither anchored to a directory fd. Between the two, an attacker can replace a path component with a symlink, redirecting the write. **Impact:** an attacker with concurrent write access to the destination tree can redirect a privileged `install -D` to an arbitrary location, enabling arbitrary file overwrite with attacker-controlled content. Recommendation: use dirfd-based traversal (`openat`/`mkdirat` + `O_NOFOLLOW`) per component and create the destination via `openat` on the same dirfd. **Remediation:** Acknowledged by Canonical; fixed in commit 0c412999. --- _Reported by Zellic in the *uutils coreutils Program Security Assessment* (prepared for Canonical, Jan 20 2026), audited commit `3a07ffc5a9bd4c283e75afa548ba1f1957bad242`. Finding 3.51. Credit: Zellic._

CVE-2026-35356 Affected install -D Versions

1 component(s)
Fixed Versions:
0.7.0
Product / Package Ecosystem Affected Versions Fixed Version
uu_install
 crates.io
< 0.7.0
0.7.0

References

GitHub Advisory / Wiki ADVISORY
https://github.com/uutils/coreutils/security/advisories/GHSA-gwm6-q8ch-hcfr
NVD — CVE-2026-35356 NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-35356
install -D Source Repository REPOSITORY
https://github.com/uutils/coreutils/pull/10140
Security Fix Commit FIX COMMIT
https://github.com/uutils/coreutils/commit/0c41299975f3c1e21cf5ca968d42cad55ceb42a1
install -D Source Repository REPOSITORY
https://github.com/uutils/coreutils
install -D Release RELEASE
https://github.com/uutils/coreutils/releases/tag/0.7.0

Frequently Asked Questions

What is CVE-2026-35356?
CVE-2026-35356 is a security vulnerability in install -D involving symlink race in directory creation allows arbitrary file overwrite under CWE-367: Time-of-check Time-of-use (TOCTOU) Race Condition.
Which install -D versions are affected?
Affected versions include releases prior to 0.7.0 across affected packages: uu_install.
What version fixes CVE-2026-35356?
Upgrading to 0.7.0 (or the latest patched release for your respective branch) resolves the vulnerability.
Is uu_install affected?
Yes, uu_install is affected in releases prior to 0.7.0. Upgrade your dependency to 0.7.0 or later.
What is the CVSS score of CVE-2026-35356?
CVE-2026-35356 has a CVSS v3.1 base score of 6.3 (MODERATE) with vector string CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:H/A:H.
What CWE is associated with CVE-2026-35356?
CVE-2026-35356 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-2026-35356?
Run the dependency tree command: 'inspect dependencies for uu_install'. 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-gwm6-q8ch-hcfr",
  "modified" : "2026-07-06T19:54:56Z",
  "published" : "2026-07-06T19:54:56Z",
  "aliases" : [ "CVE-2026-35356" ],
  "summary" : "install -D: symlink race in directory creation allows arbitrary file overwrite",
  "details" : "The `-D` path runs `fs::create_dir_all` on a pathname then later opens the destination via path-based `File::create`/`fs::copy`, neither anchored to a directory fd. Between the two, an attacker can replace a path component with a symlink, redirecting the write.\n\n**Impact:** an attacker with concurrent write access to the destination tree can redirect a privileged `install -D` to an arbitrary location, enabling arbitrary file overwrite with attacker-controlled content. Recommendation: use dirfd-based traversal (`openat`/`mkdirat` + `O_NOFOLLOW`) per component and create the destination via `openat` on the same dirfd.\n\n**Remediation:** Acknowledged by Canonical; fixed in commit 0c412999.\n\n---\n_Reported by Zellic in the *uutils coreutils Program Security Assessment* (prepared for Canonical, Jan 20 2026), audited commit `3a07ffc5a9bd4c283e75afa548ba1f1957bad242`. Finding 3.51. Credit: Zellic._",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:H/A:H"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "crates.io",
      "name" : "uu_install"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "0.7.0"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/uutils/coreutils/security/advisories/GHSA-gwm6-q8ch-hcfr"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-35356"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/uutils/coreutils/pull/10140"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/uutils/coreutils/commit/0c41299975f3c1e21cf5ca968d42cad55ceb42a1"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/uutils/coreutils"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/uutils/coreutils/releases/tag/0.7.0"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-367", "CWE-59" ],
    "severity" : "MODERATE",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-07-06T19:54:56Z",
    "nvd_published_at" : null
  }
}