CVE-2021-29487: October/system October CMS Auth Bypass And Vulnerability

HIGH
Advisory Identifier: GHSA-h76r-vgf3-j6w5
CVSS 7.4
CWE-287
Published
Advisory Summary

CVE-2021-29487 is a HIGH (CVSS 7.4) october cms auth bypass and vulnerability (CWE-287: Improper Authentication) affecting October/system libraries in the Packagist ecosystem. The issue involves october cms auth bypass and account takeover. Remediation is available by upgrading affected packages to version 1.0.472, 1.1.5.

CVE-2021-29487 at a Glance

CVE Identifier CVE-2021-29487
GHSA Identifier GHSA-h76r-vgf3-j6w5
Severity HIGH
CVSS v3.1 Base Score 7.4
CWE Classification CWE-287: Improper Authentication
Affected Product October/system
Package Ecosystem Packagist
Published Date
Last Updated

Security Impact

CVSS: 7.4

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

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

How to Fix CVE-2021-29487

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

october/system fixed: 1.0.472
Upgrade october/system to 1.0.472
october/system fixed: 1.1.5
Upgrade october/system to 1.1.5
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 october/system

How to Check if You Are Affected

To determine whether your application is affected by CVE-2021-29487, inspect your project dependencies for October/system:

inspect dependencies for october/system

Analyze the terminal output to locate any version of October/system in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 1.0.472), 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-287: Improper Authentication, where when an actor claims to have a given identity, the product does not prove or insufficiently proves that the claim is correct. In October/system, 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 An attacker can exploit this vulnerability to bypass authentication using a specially crafted persist cookie. - To exploit this vulnerability, an attacker must obtain a Laravel’s secret key for cookie encryption and signing. - Due to the logic of how this mechanism works, a targeted user account must be logged in while the attacker is exploiting the vulnerability. - Authorization via persist cookie not shown in access logs. ### Patches - Issue has been patched in Build 472 and v1.1.5 - [Shortened patch instructions](https://github.com/daftspunk/CVE-2021-32648) ### Workarounds Apply https://github.com/octobercms/library/commit/016a297b1bec55d2e53bc889458ed2cb5c3e9374 and https://github.com/octobercms/library/commit/5bd1a28140b825baebe6becd4f7562299d3de3b9 to your installation manually if you are unable to upgrade. [**Update 2022-01-20**] [Shortened patch instructions](https://github.com/daftspunk/CVE-2021-32648) can be found here. ### Recommendations We recommend the following steps to make sure your server stays secure: - Keep server OS and system software up to date. - Keep October CMS software up to date. - Use a multi-factor authentication plugin. - Change the [default backend URL](https://github.com/octobercms/october/blob/1.1/config/cms.php#L39) or block public access to the backend area. - Include the [Roave/SecurityAdvisories](https://github.com/Roave/SecurityAdvisories) Composer package to ensure that your application doesn't have installed dependencies with known security vulnerabilities. ### References Bugs found as part of Solar Security CMS Research. Credits to: • Andrey Basarygin • Andrey Guzei • Mikhail Khramenkov • Alexander Sidukov • Maxim Teplykh ### For more information If you have any questions or comments about this advisory: * Email us at [hello@octobercms.com](mailto:hello@octobercms.com)

CVE-2021-29487 Affected October/system Versions

2 component(s)
Fixed Versions:
1.0.4721.1.5
Product / Package Ecosystem Affected Versions Fixed Version
october/system
Packagist
< 1.0.472
1.0.472
october/system
Packagist
≥ 1.1.1
< 1.1.5
1.1.5

References

Frequently Asked Questions

What is CVE-2021-29487?
CVE-2021-29487 is a security vulnerability in October/system involving October CMS auth bypass and account takeover under CWE-287: Improper Authentication.
Which October/system versions are affected?
Affected versions include releases prior to 1.0.472, 1.1.5 across affected packages: october/system.
What version fixes CVE-2021-29487?
Upgrading to 1.0.472, 1.1.5 (or the latest patched release for your respective branch) resolves the vulnerability.
Is october/system affected?
Yes, october/system is affected in releases prior to 1.0.472, 1.1.5. Upgrade your dependency to 1.0.472, 1.1.5 or later.
What is the CVSS score of CVE-2021-29487?
CVE-2021-29487 has a CVSS v3.1 base score of 7.4 (HIGH) with vector string CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N.
What CWE is associated with CVE-2021-29487?
CVE-2021-29487 is classified under CWE-287: Improper Authentication (When an actor claims to have a given identity, the product does not prove or insufficiently proves that the claim is correct.).
How can I check Packagist dependencies for CVE-2021-29487?
Run the dependency tree command: 'inspect dependencies for october/system'. 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-h76r-vgf3-j6w5",
  "modified" : "2022-08-11T00:18:28Z",
  "published" : "2021-08-30T16:13:50Z",
  "aliases" : [ "CVE-2021-29487" ],
  "summary" : "October CMS auth bypass and account takeover",
  "details" : "### Impact\n\nAn attacker can exploit this vulnerability to bypass authentication using a specially crafted persist cookie.\n\n- To exploit this vulnerability, an attacker must obtain a Laravel’s secret key for cookie encryption and signing.\n- Due to the logic of how this mechanism works, a targeted user account must be logged in while\nthe attacker is exploiting the vulnerability.\n- Authorization via persist cookie not shown in access logs.\n\n### Patches\n\n- Issue has been patched in Build 472 and v1.1.5\n- [Shortened patch instructions](https://github.com/daftspunk/CVE-2021-32648)\n\n### Workarounds\n\nApply https://github.com/octobercms/library/commit/016a297b1bec55d2e53bc889458ed2cb5c3e9374 and https://github.com/octobercms/library/commit/5bd1a28140b825baebe6becd4f7562299d3de3b9 to your installation manually if you are unable to upgrade.\n\n[**Update 2022-01-20**] [Shortened patch instructions](https://github.com/daftspunk/CVE-2021-32648) can be found here.\n\n### Recommendations\n\nWe recommend the following steps to make sure your server stays secure:\n\n- Keep server OS and system software up to date.\n- Keep October CMS software up to date.\n- Use a multi-factor authentication plugin.\n- Change the [default backend URL](https://github.com/octobercms/october/blob/1.1/config/cms.php#L39) or block public access to the backend area.\n- Include the [Roave/SecurityAdvisories](https://github.com/Roave/SecurityAdvisories) Composer package to ensure that your application doesn't have installed dependencies with known security vulnerabilities.\n\n### References\n\nBugs found as part of Solar Security CMS Research. Credits to:\n• Andrey Basarygin\n• Andrey Guzei\n• Mikhail Khramenkov\n• Alexander Sidukov\n• Maxim Teplykh\n\n### For more information\nIf you have any questions or comments about this advisory:\n* Email us at [hello@octobercms.com](mailto:hello@octobercms.com)\n",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "Packagist",
      "name" : "october/system"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "1.0.472"
      } ]
    } ]
  }, {
    "package" : {
      "ecosystem" : "Packagist",
      "name" : "october/system"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "1.1.1"
      }, {
        "fixed" : "1.1.5"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/octobercms/october/security/advisories/GHSA-h76r-vgf3-j6w5"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2021-29487"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/octobercms/library/commit/016a297b1bec55d2e53bc889458ed2cb5c3e9374"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/octobercms/library/commit/5bd1a28140b825baebe6becd4f7562299d3de3b9"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/octobercms/october"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-287" ],
    "severity" : "HIGH",
    "github_reviewed" : true,
    "github_reviewed_at" : "2021-08-26T20:09:50Z",
    "nvd_published_at" : "2021-08-26T19:15:00Z"
  }
}