CVE-2020-26136: Silverstripe/graphql Authentication Bypass Vulnerability

MODERATE
Advisory Identifier: GHSA-mg2g-8pwj-r2j2
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CVSS 6.5
CWE-287 CWE-288
Published
Advisory Summary

CVE-2020-26136 is a MODERATE (CVSS 6.5) authentication bypass vulnerability (CWE-287: Improper Authentication) affecting Silverstripe/graphql libraries in the Packagist ecosystem. The issue involves authentication bypass in silverstripe graphql. Remediation is available by upgrading affected packages to version 3.5.0, 4.0.0-alpha2.

CVE-2020-26136 at a Glance

CVE Identifier CVE-2020-26136
GHSA Identifier GHSA-mg2g-8pwj-r2j2
Severity MODERATE
CVSS v3.1 Base Score 6.5
CWE Classification CWE-287: Improper Authentication
Affected Product Silverstripe/graphql
Package Ecosystem Packagist
Published Date
Last Updated

Security Impact

CVSS: 6.5

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

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

How to Fix CVE-2020-26136

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

silverstripe/graphql fixed: 3.5.0 
Upgrade silverstripe/graphql to 3.5.0
silverstripe/graphql fixed: 4.0.0-alpha2 
Upgrade silverstripe/graphql to 4.0.0-alpha2
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 silverstripe/graphql

How to Check if You Are Affected

To determine whether your application is affected by CVE-2020-26136, inspect your project dependencies for Silverstripe/graphql:

inspect dependencies for silverstripe/graphql

Analyze the terminal output to locate any version of Silverstripe/graphql in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 3.5.0), 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-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 Silverstripe/graphql, 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 GraphQL module accepts basic-auth as an authentication method by default. This can be used to bypass MFA authentication if the silverstripe/mfa module is installed, which is now a commonly installed module. A users password is still required though. Basic-auth has been removed as a default authentication method. If desired, it can be re-enabled by adding it to the authenticators key of a schema, or on SilverStripe\Graphql\Auth\Handler

CVE-2020-26136 Affected Silverstripe/graphql Versions

2 component(s)
Fixed Versions:
3.5.04.0.0-alpha2
Product / Package Ecosystem Affected Versions Fixed Version
silverstripe/graphql
 Packagist
≥ 3.0.0
< 3.5.0
3.5.0
silverstripe/graphql
 Packagist
≥ 4.0.0-alpha1
< 4.0.0-alpha2
4.0.0-alpha2

References

NVD — CVE-2020-26136 NVD
https://nvd.nist.gov/vuln/detail/CVE-2020-26136
forum.silverstripe.org/c/releases WEB
https://forum.silverstripe.org/c/releases
Silverstripe/graphql Source Repository REPOSITORY
https://github.com/FriendsOfPHP/security-advisories/blob/master/silverstripe/graphql/CVE-2020-26136.yaml
www.silverstripe.org/blog/tag/release WEB
https://www.silverstripe.org/blog/tag/release
Silverstripe/graphql Release RELEASE
https://www.silverstripe.org/download/security-releases
Silverstripe/graphql Release RELEASE
https://www.silverstripe.org/download/security-releases/cve-2020-26136

Frequently Asked Questions

What is CVE-2020-26136?
CVE-2020-26136 is a security vulnerability in Silverstripe/graphql involving Authentication bypass in SilverStripe GraphQL under CWE-287: Improper Authentication.
Which Silverstripe/graphql versions are affected?
Affected versions include releases prior to 3.5.0, 4.0.0-alpha2 across affected packages: silverstripe/graphql.
What version fixes CVE-2020-26136?
Upgrading to 3.5.0, 4.0.0-alpha2 (or the latest patched release for your respective branch) resolves the vulnerability.
Is silverstripe/graphql affected?
Yes, silverstripe/graphql is affected in releases prior to 3.5.0, 4.0.0-alpha2. Upgrade your dependency to 3.5.0, 4.0.0-alpha2 or later.
What is the CVSS score of CVE-2020-26136?
CVE-2020-26136 has a CVSS v3.1 base score of 6.5 (MODERATE) with vector string CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N.
What CWE is associated with CVE-2020-26136?
CVE-2020-26136 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-2020-26136?
Run the dependency tree command: 'inspect dependencies for silverstripe/graphql'. 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-mg2g-8pwj-r2j2",
  "modified" : "2022-03-15T16:38:13Z",
  "published" : "2021-06-10T17:21:33Z",
  "aliases" : [ "CVE-2020-26136" ],
  "summary" : "Authentication bypass in SilverStripe GraphQL",
  "details" : "The GraphQL module accepts basic-auth as an authentication method by default. This can be used to bypass MFA authentication if the silverstripe/mfa module is installed, which is now a commonly installed module. A users password is still required though.\n\nBasic-auth has been removed as a default authentication method. If desired, it can be re-enabled by adding it to the authenticators key of a schema, or on SilverStripe\\Graphql\\Auth\\Handler",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "Packagist",
      "name" : "silverstripe/graphql"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "3.0.0"
      }, {
        "fixed" : "3.5.0"
      } ]
    } ]
  }, {
    "package" : {
      "ecosystem" : "Packagist",
      "name" : "silverstripe/graphql"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "4.0.0-alpha1"
      }, {
        "fixed" : "4.0.0-alpha2"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2020-26136"
  }, {
    "type" : "WEB",
    "url" : "https://forum.silverstripe.org/c/releases"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/FriendsOfPHP/security-advisories/blob/master/silverstripe/graphql/CVE-2020-26136.yaml"
  }, {
    "type" : "WEB",
    "url" : "https://www.silverstripe.org/blog/tag/release"
  }, {
    "type" : "WEB",
    "url" : "https://www.silverstripe.org/download/security-releases"
  }, {
    "type" : "WEB",
    "url" : "https://www.silverstripe.org/download/security-releases/cve-2020-26136"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-287", "CWE-288" ],
    "severity" : "MODERATE",
    "github_reviewed" : true,
    "github_reviewed_at" : "2021-06-10T14:41:10Z",
    "nvd_published_at" : "2021-06-08T20:15:00Z"
  }
}