CVE-2021-44528: Actionpack Actionpack Open Redirect Vulnerability

Q: What is CVE-2021-44528?

CVE-2021-44528 is a security vulnerability in Actionpack involving actionpack Open Redirect in Host Authorization Middleware under CWE-601: URL Redirection to Untrusted Site ('Open Redirect').

Q: Which Actionpack versions are affected?

Affected versions include releases prior to 6.0.4.2, 6.1.4.2 across affected packages: actionpack.

Q: What version fixes CVE-2021-44528?

Upgrading to 6.0.4.2, 6.1.4.2 (or the latest patched release for your respective branch) resolves the vulnerability.

Q: Is actionpack affected?

Yes, actionpack is affected in releases prior to 6.0.4.2, 6.1.4.2. Upgrade your dependency to 6.0.4.2, 6.1.4.2 or later.

Q: What is the CVSS score of CVE-2021-44528?

CVE-2021-44528 has a CVSS v3.1 base score of 6.1 (MODERATE) with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N.

Q: What CWE is associated with CVE-2021-44528?

CVE-2021-44528 is classified under CWE-601: URL Redirection to Untrusted Site ('Open Redirect') (The web application accepts a user-controlled input that specifies a link to an external site, and uses that link in a redirect.).

Q: How can I check RubyGems dependencies for CVE-2021-44528?

Run the dependency tree command: 'inspect dependencies for actionpack'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.

MODERATE

Advisory Identifier: GHSA-qphc-hf5q-v8fc

CVSS 6.1

CWE-601

Published 2021-12-14

Advisory Summary

CVE-2021-44528 is a MODERATE (CVSS 6.1) actionpack open redirect vulnerability (CWE-601: URL Redirection to Untrusted Site ('Open Redirect')) affecting Actionpack libraries in the RubyGems ecosystem. The issue involves actionpack open redirect in host authorization middleware. Remediation is available by upgrading affected packages to version 6.0.4.2, 6.1.4.2.

CVE-2021-44528 at a Glance

CVE Identifier CVE-2021-44528

GHSA Identifier GHSA-qphc-hf5q-v8fc

Severity MODERATE

CVSS v3.1 Base Score 6.1

CWE Classification CWE-601: URL Redirection to Untrusted Site ('Open Redirect')

Affected Product Actionpack

Package Ecosystem RubyGems

Published Date 2021-12-14

Last Updated 2024-02-08

Security Impact

CVSS: 6.1

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:R/S:C/C:L/I:L/A:N).

Attack Vector Network (AV:N)

Attack Complexity Low (AC:L)

Privileges Required None (PR:N)

User Interaction Required (UI:R)

Scope Changed (S:C)

Confidentiality Low (C:L)

Integrity Low (I:L)

Availability None (A:N)

How to Fix CVE-2021-44528

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

actionpack fixed: 6.0.4.2

Upgrade actionpack to 6.0.4.2

actionpack fixed: 6.1.4.2

Upgrade actionpack to 6.1.4.2

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 actionpack

How to Check if You Are Affected

To determine whether your application is affected by CVE-2021-44528, inspect your project dependencies for Actionpack:

inspect dependencies for actionpack

Analyze the terminal output to locate any version of Actionpack in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 6.0.4.2), 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-601: URL Redirection to Untrusted Site ('Open Redirect'), where the web application accepts a user-controlled input that specifies a link to an external site, and uses that link in a redirect. In Actionpack, 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

Specially crafted "X-Forwarded-Host" headers in combination with certain "allowed host" formats can cause the Host Authorization middleware in Action Pack to redirect users to a malicious website. Impacted applications will have allowed hosts with a leading dot. For example, configuration files that look like this: ``` config.hosts << '.EXAMPLE.com' ``` When an allowed host contains a leading dot, a specially crafted Host header can be used to redirect to a malicious website. This vulnerability is similar to CVE-2021-22881 and CVE-2021-22942. Releases -------- The fixed releases are available at the normal locations. Patches ------- To aid users who aren't able to upgrade immediately we have provided patches for the two supported release series. They are in git-am format and consist of a single changeset. * 6-0-host-authorzation-open-redirect.patch - Patch for 6.0 series * 6-1-host-authorzation-open-redirect.patch - Patch for 6.1 series * 7-0-host-authorzation-open-redirect.patch - Patch for 7.0 series Please note that only the 6.1.Z, 6.0.Z, and 5.2.Z series are supported at present. Users of earlier unsupported releases are advised to upgrade as soon as possible as we cannot guarantee the continued availability of security fixes for unsupported releases.

CVE-2021-44528 Affected Actionpack Versions

2 component(s)

Fixed Versions:

6.0.4.26.1.4.2

Product / Package	Ecosystem	Affected Versions	Fixed Version
actionpack gem/actionpack	RubyGems	≥ 6.0.0 < 6.0.4.2	6.0.4.2
actionpack gem/actionpack	RubyGems	≥ 6.1.0 < 6.1.4.2	6.1.4.2

References

NVD — CVE-2021-44528 NVD

https://nvd.nist.gov/vuln/detail/CVE-2021-44528

Security Fix Commit FIX COMMIT

https://github.com/rails/rails/commit/0fccfb9a3097a9c4260c791f1a40b128517e7815

Security Fix Commit FIX COMMIT

https://github.com/rails/rails/commit/aecba3c301b80e9d5a63c30ea1b287bceaf2c107

Actionpack Source Repository REPOSITORY

https://github.com/rails/rails

Actionpack Source Repository REPOSITORY

https://github.com/rails/rails/blob/v6.1.4.2/actionpack/CHANGELOG.md#rails-6142-december-14-2021

Actionpack Source Repository REPOSITORY

https://github.com/rubysec/ruby-advisory-db/blob/master/gems/actionpack/CVE-2021-44528.yml

Actionpack Security Information SECURITY

https://groups.google.com/g/ruby-security-ann/c/vG9gz3nk1pM/m/7-NU4MNrDAAJ

Actionpack Security Information SECURITY

https://groups.google.com/g/ruby-security-ann/c/vG9gz3nk1pM/m/7-NU4MNrDAAJ?utm_medium=email&utm_source=footer

Actionpack Security Information SECURITY

https://security.netapp.com/advisory/ntap-20240208-0003

Actionpack Security Information SECURITY

https://www.debian.org/security/2023/dsa-5372

Frequently Asked Questions

What is CVE-2021-44528?

CVE-2021-44528 is a security vulnerability in Actionpack involving actionpack Open Redirect in Host Authorization Middleware under CWE-601: URL Redirection to Untrusted Site ('Open Redirect').

Which Actionpack versions are affected?

Affected versions include releases prior to 6.0.4.2, 6.1.4.2 across affected packages: actionpack.

What version fixes CVE-2021-44528?

Upgrading to 6.0.4.2, 6.1.4.2 (or the latest patched release for your respective branch) resolves the vulnerability.

Is actionpack affected?

Yes, actionpack is affected in releases prior to 6.0.4.2, 6.1.4.2. Upgrade your dependency to 6.0.4.2, 6.1.4.2 or later.

What is the CVSS score of CVE-2021-44528?

CVE-2021-44528 has a CVSS v3.1 base score of 6.1 (MODERATE) with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N.

What CWE is associated with CVE-2021-44528?

CVE-2021-44528 is classified under CWE-601: URL Redirection to Untrusted Site ('Open Redirect') (The web application accepts a user-controlled input that specifies a link to an external site, and uses that link in a redirect.).

How can I check RubyGems dependencies for CVE-2021-44528?

Run the dependency tree command: 'inspect dependencies for actionpack'. 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-qphc-hf5q-v8fc",
  "modified" : "2024-02-08T12:30:47Z",
  "published" : "2021-12-14T21:19:08Z",
  "aliases" : [ "CVE-2021-44528" ],
  "summary" : "actionpack Open Redirect in Host Authorization Middleware",
  "details" : "Specially crafted \"X-Forwarded-Host\" headers in combination with certain \"allowed host\" formats can cause the Host Authorization middleware in Action Pack to redirect users to a malicious website.\n\nImpacted applications will have allowed hosts with a leading dot. For example, configuration files that look like this:\n\n```\nconfig.hosts <<  '.EXAMPLE.com'\n```\n\nWhen an allowed host contains a leading dot, a specially crafted Host header can be used to redirect to a malicious website.\n\nThis vulnerability is similar to CVE-2021-22881 and CVE-2021-22942.\n\nReleases\n--------\nThe fixed releases are available at the normal locations.\n\nPatches\n-------\nTo aid users who aren't able to upgrade immediately we have provided patches for the two supported release series. They are in git-am format and consist of a single changeset.\n\n* 6-0-host-authorzation-open-redirect.patch - Patch for 6.0 series\n* 6-1-host-authorzation-open-redirect.patch - Patch for 6.1 series\n* 7-0-host-authorzation-open-redirect.patch - Patch for 7.0 series\n\nPlease note that only the 6.1.Z, 6.0.Z, and 5.2.Z series are supported at present. Users of earlier unsupported releases are advised to upgrade as soon as possible as we cannot guarantee the continued availability of security fixes for unsupported releases.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "RubyGems",
      "name" : "actionpack"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "6.0.0"
      }, {
        "fixed" : "6.0.4.2"
      } ]
    } ],
    "database_specific" : {
      "last_known_affected_version_range" : "<= 6.0.4.1"
    }
  }, {
    "package" : {
      "ecosystem" : "RubyGems",
      "name" : "actionpack"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "6.1.0"
      }, {
        "fixed" : "6.1.4.2"
      } ]
    } ],
    "database_specific" : {
      "last_known_affected_version_range" : "<= 6.1.4.1"
    }
  } ],
  "references" : [ {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2021-44528"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/rails/rails/commit/0fccfb9a3097a9c4260c791f1a40b128517e7815"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/rails/rails/commit/aecba3c301b80e9d5a63c30ea1b287bceaf2c107"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/rails/rails"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/rails/rails/blob/v6.1.4.2/actionpack/CHANGELOG.md#rails-6142-december-14-2021"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/rubysec/ruby-advisory-db/blob/master/gems/actionpack/CVE-2021-44528.yml"
  }, {
    "type" : "WEB",
    "url" : "https://groups.google.com/g/ruby-security-ann/c/vG9gz3nk1pM/m/7-NU4MNrDAAJ"
  }, {
    "type" : "WEB",
    "url" : "https://groups.google.com/g/ruby-security-ann/c/vG9gz3nk1pM/m/7-NU4MNrDAAJ?utm_medium=email&utm_source=footer"
  }, {
    "type" : "WEB",
    "url" : "https://security.netapp.com/advisory/ntap-20240208-0003"
  }, {
    "type" : "WEB",
    "url" : "https://www.debian.org/security/2023/dsa-5372"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-601" ],
    "severity" : "MODERATE",
    "github_reviewed" : true,
    "github_reviewed_at" : "2021-12-14T21:12:06Z",
    "nvd_published_at" : "2022-01-10T14:10:00Z"
  }
}

CVSS V3

6.1 MODERATE

Attack Vector Network (AV:N)

Attack Complexity Low (AC:L)

Privileges Required None (PR:N)

User Interaction Required (UI:R)

Scope Changed (S:C)

Confidentiality Low (C:L)

Integrity Low (I:L)

Availability None (A:N)

Vector String

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

Advisory Metadata

Source ID: GHSA-qphc-hf5q-v8fc
Schema Version: 1.4.0
Published: 2021-12-14 21:19
Last Modified: 2024-02-08 12:30
Database Record File: advisories/github-reviewed/2021/12/GHSA-qphc-hf5q-v8fc/GHSA-qphc-hf5q-v8fc.json