CVE-2018-12027: Passenger Insecure Permissions Vulnerability

HIGH
Advisory Identifier: GHSA-whfx-877c-5p28
CVSS 8.8
CWE-200
Published
Advisory Summary

CVE-2018-12027 is a HIGH (CVSS 8.8) insecure permissions vulnerability (CWE-200: Exposure of Sensitive Information to an Unauthorized Actor) affecting Passenger libraries in the RubyGems ecosystem. The issue involves insecure permissions in phusion passenger. Remediation is available by upgrading affected packages to version 5.3.2.

CVE-2018-12027 at a Glance

CVE Identifier CVE-2018-12027
GHSA Identifier GHSA-whfx-877c-5p28
Severity HIGH
CVSS v3.1 Base Score 8.8
CWE Classification CWE-200: Exposure of Sensitive Information to an Unauthorized Actor
Affected Product Passenger
Package Ecosystem RubyGems
Published Date
Last Updated

Security Impact

CVSS: 8.8

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

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

How to Fix CVE-2018-12027

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

passenger fixed: 5.3.2
Upgrade passenger to 5.3.2
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 passenger

How to Check if You Are Affected

To determine whether your application is affected by CVE-2018-12027, inspect your project dependencies for Passenger:

inspect dependencies for passenger

Analyze the terminal output to locate any version of Passenger in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 5.3.2), 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-200: Exposure of Sensitive Information to an Unauthorized Actor, where the product exposes sensitive information to an actor that is not explicitly authorized to have access to that information. In Passenger, 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

An Insecure Permissions vulnerability in SpawningKit in Phusion Passenger 5.3.x before 5.3.2 causes information disclosure in the following situation: given a Passenger-spawned application process that reports that it listens on a certain Unix domain socket, if any of the parent directories of said socket are writable by a normal user that is not the application's user, then that non-application user can swap that directory with something else, resulting in traffic being redirected to a non-application user's process through an alternative Unix domain socket.

CVE-2018-12027 Affected Passenger Versions

1 component(s)
Fixed Versions:
5.3.2
Product / Package Ecosystem Affected Versions Fixed Version
passenger
RubyGems
≥ 5.3.0
< 5.3.2
5.3.2

References

Frequently Asked Questions

What is CVE-2018-12027?
CVE-2018-12027 is a security vulnerability in Passenger involving Insecure Permissions in Phusion Passenger under CWE-200: Exposure of Sensitive Information to an Unauthorized Actor.
Which Passenger versions are affected?
Affected versions include releases prior to 5.3.2 across affected packages: passenger.
What version fixes CVE-2018-12027?
Upgrading to 5.3.2 (or the latest patched release for your respective branch) resolves the vulnerability.
Is passenger affected?
Yes, passenger is affected in releases prior to 5.3.2. Upgrade your dependency to 5.3.2 or later.
What is the CVSS score of CVE-2018-12027?
CVE-2018-12027 has a CVSS v3.1 base score of 8.8 (HIGH) with vector string CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.
What CWE is associated with CVE-2018-12027?
CVE-2018-12027 is classified under CWE-200: Exposure of Sensitive Information to an Unauthorized Actor (The product exposes sensitive information to an actor that is not explicitly authorized to have access to that information.).
How can I check RubyGems dependencies for CVE-2018-12027?
Run the dependency tree command: 'inspect dependencies for passenger'. 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-whfx-877c-5p28",
  "modified" : "2023-06-28T20:13:40Z",
  "published" : "2022-05-13T01:49:24Z",
  "aliases" : [ "CVE-2018-12027" ],
  "summary" : "Insecure Permissions in Phusion Passenger",
  "details" : "An Insecure Permissions vulnerability in SpawningKit in Phusion Passenger 5.3.x before 5.3.2 causes information disclosure in the following situation: given a Passenger-spawned application process that reports that it listens on a certain Unix domain socket, if any of the parent directories of said socket are writable by a normal user that is not the application's user, then that non-application user can swap that directory with something else, resulting in traffic being redirected to a non-application user's process through an alternative Unix domain socket.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "RubyGems",
      "name" : "passenger"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "5.3.0"
      }, {
        "fixed" : "5.3.2"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2018-12027"
  }, {
    "type" : "WEB",
    "url" : "https://blog.phusion.nl/passenger-5-3-2"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/phusion/passenger"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/rubysec/ruby-advisory-db/blob/master/gems/passenger/CVE-2018-12027.yml"
  }, {
    "type" : "WEB",
    "url" : "https://security.gentoo.org/glsa/201807-02"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-200" ],
    "severity" : "HIGH",
    "github_reviewed" : true,
    "github_reviewed_at" : "2023-06-09T22:59:06Z",
    "nvd_published_at" : "2018-06-17T20:29:00Z"
  }
}