GHSA-j68w-pg49-f6vx: Symfony/serializer Symfony XML Decoding Attack Vector Vulnerability

CRITICAL
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CVSS 9.8
CWE-611
Published
Advisory Summary

GHSA-j68w-pg49-f6vx is a CRITICAL (CVSS 9.8) symfony xml decoding attack vector vulnerability (CWE-611: Improper Restriction of XML External Entity Reference) affecting Symfony/serializer libraries in the Packagist ecosystem. The issue involves symfony xml decoding attack vector through external entities. Remediation is available by upgrading affected packages to version 2.0.11.

GHSA-j68w-pg49-f6vx at a Glance

CVE Identifier N/A
GHSA Identifier GHSA-j68w-pg49-f6vx
Severity CRITICAL
CVSS v3.1 Base Score 9.8
CWE Classification CWE-611: Improper Restriction of XML External Entity Reference
Affected Product Symfony/serializer
Package Ecosystem Packagist
Published Date
Last Updated

Security Impact

CVSS: 9.8

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:N/S:U/C:H/I:H/A:H).

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

How to Fix GHSA-j68w-pg49-f6vx

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

symfony/serializer fixed: 2.0.11 
Upgrade symfony/serializer to 2.0.11
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 symfony/serializer

How to Check if You Are Affected

To determine whether your application is affected by GHSA-j68w-pg49-f6vx, inspect your project dependencies for Symfony/serializer:

inspect dependencies for symfony/serializer

Analyze the terminal output to locate any version of Symfony/serializer in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 2.0.11), 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-611: Improper Restriction of XML External Entity Reference, where the product processes an xml document that can contain xml entities with uris that resolve to documents outside of the intended sphere of control, causing the product to embed incorrect documents into its output. In Symfony/serializer, 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 XMLEncoder component of Symfony 2.0.x fails to disable external entities when parsing XML. In the Symfony2 framework the XML class may be used to deserialize objects or as part of a client/server API. By using external entities it is possible to include arbitrary files from the file system.

GHSA-j68w-pg49-f6vx Affected Symfony/serializer Versions

1 component(s)
Fixed Versions:
2.0.11
Product / Package Ecosystem Affected Versions Fixed Version
symfony/serializer
 Packagist
≥ 2.0.0
< 2.0.11
2.0.11

References

Security Fix Commit FIX COMMIT
https://github.com/symfony/serializer/commit/0943a06a663b573d7319fc1acd56d3484eaaa430
Symfony/serializer Source Repository REPOSITORY
https://github.com/FriendsOfPHP/security-advisories/blob/master/symfony/serializer/2012-02-24.yaml
Symfony/serializer Source Repository REPOSITORY
https://github.com/symfony/serializer
Symfony/serializer Release RELEASE
https://symfony.com/blog/security-release-symfony-2-0-11-released

Frequently Asked Questions

What is GHSA-j68w-pg49-f6vx?
GHSA-j68w-pg49-f6vx is a security vulnerability in Symfony/serializer involving Symfony XML decoding attack vector through external entities under CWE-611: Improper Restriction of XML External Entity Reference.
Which Symfony/serializer versions are affected?
Affected versions include releases prior to 2.0.11 across affected packages: symfony/serializer.
What version fixes GHSA-j68w-pg49-f6vx?
Upgrading to 2.0.11 (or the latest patched release for your respective branch) resolves the vulnerability.
Is symfony/serializer affected?
Yes, symfony/serializer is affected in releases prior to 2.0.11. Upgrade your dependency to 2.0.11 or later.
What is the CVSS score of GHSA-j68w-pg49-f6vx?
GHSA-j68w-pg49-f6vx has a CVSS v3.1 base score of 9.8 (CRITICAL) with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.
What CWE is associated with GHSA-j68w-pg49-f6vx?
GHSA-j68w-pg49-f6vx is classified under CWE-611: Improper Restriction of XML External Entity Reference (The product processes an XML document that can contain XML entities with URIs that resolve to documents outside of the intended sphere of control, causing the product to embed incorrect documents into its output.).
How can I check Packagist dependencies for GHSA-j68w-pg49-f6vx?
Run the dependency tree command: 'inspect dependencies for symfony/serializer'. 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-j68w-pg49-f6vx",
  "modified" : "2024-05-30T00:52:20Z",
  "published" : "2024-05-30T00:52:20Z",
  "aliases" : [ ],
  "summary" : "Symfony XML decoding attack vector through external entities",
  "details" : "The XMLEncoder component of Symfony 2.0.x fails to disable external entities when parsing XML. In the Symfony2 framework the XML class may be used to deserialize objects or as part of a client/server API. By using external entities it is possible to include arbitrary files from the file system.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "Packagist",
      "name" : "symfony/serializer"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "2.0.0"
      }, {
        "fixed" : "2.0.11"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/symfony/serializer/commit/0943a06a663b573d7319fc1acd56d3484eaaa430"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/FriendsOfPHP/security-advisories/blob/master/symfony/serializer/2012-02-24.yaml"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/symfony/serializer"
  }, {
    "type" : "WEB",
    "url" : "https://symfony.com/blog/security-release-symfony-2-0-11-released"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-611" ],
    "severity" : "CRITICAL",
    "github_reviewed" : true,
    "github_reviewed_at" : "2024-05-30T00:52:20Z",
    "nvd_published_at" : null
  }
}