---
id: CVE-2026-123824
title: >-
  Symfony: XXE (Local File Read) in Config XmlUtils::parse() via validateOnParse
  = true
summary: "The Symfony Config component\_XmlUtils::parse()\_enables DTD validation before rejecting documents that carry a doctype, allowing\_XML external entity (XXE) injection in Symfony versions prior to 5.4.56, 6.x prior to 6.4.50, 7.x prior to 7.…"
severity: low
cvss: 2.3
cvssVector: 'CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N'
cvssSource: cna
cwe:
  - CWE-611
vendor: sensiolabs
product: symfony/config
affected:
  - symfony/config < 5.4.56
  - symfony/config >= 6.0.0 < 6.4.50
  - symfony/config >= 7.0.0 < 7.4.23
  - symfony/config >= 8.0.0 < 8.1.11
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2026-11-06T20:28:48.074549Z'
published: '2026-11-06'
updated: '2026-11-06'
sourceUpdated: '2026-11-06T20:29:12.981Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-123824'
references:
  - url: 'https://github.com/symfony/symfony/security/advisories/GHSA-5jff-8h8q-r5qx'
  - url: >-
      https://github.com/symfony/symfony/commit/334ef21a6039355c05b123e7df60699be0e28da3
tags:
  - cve.org
ingestedAt: '2026-11-06T18:00:12.518Z'
epss: 0.00272
epssPercentile: 0.19713
---

## Overview

The Symfony Config component XmlUtils::parse() enables DTD validation before rejecting documents that carry a doctype, allowing XML external entity (XXE) injection in Symfony versions prior to 5.4.56, 6.x prior to 6.4.50, 7.x prior to 7.4.23, and 8.x prior to 8.1.11. A remote attacker who can supply XML to this method can determine whether local files exist, cause a denial of service, and, in some configurations, exfiltrate local file content via a crafted XML document whose doctype declares an external file:// entity.
XmlUtils::parse() sets $dom->validateOnParse = true before calling loadXML() and only rejects documents carrying a doctype afterwards. Enabling DTD validation makes libxml resolve external entities during loadXML(), and LIBXML_NONET blocks http:// but not file://, so a file:// entity is read from disk before the doctype rejection runs. The content of the file is not returned to the caller, but the distinct libxml error for a missing path reveals whether a file exists, and an entity pointing at a large or slow file causes a denial of service. If the application registers a network-capable stream wrapper such as s3://, a parameter entity can also send the content of a local file to an external server. This is the same issue as CVE-2026-45071, which was fixed in the DomCrawler component but not in Config.

Applications are affected if they pass untrusted XML to XmlUtils::parse() directly. The Symfony components that call it process developer-provided or operator-configured sources, such as configuration files and the XLIFF documents fetched by the translation providers.

## Affected

- `symfony/config < 5.4.56`
- `symfony/config >= 6.0.0 < 6.4.50`
- `symfony/config >= 7.0.0 < 7.4.23`
- `symfony/config >= 8.0.0 < 8.1.11`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.