CVE-2026-45071
Symfony has XXE (Local File Disclosure) in DomCrawler::addXmlContent() via validateOnParse = true
Description
### Description `symfony/dom-crawler` provides the `Crawler` class for navigating HTML/XML documents with CSS/XPath selectors; `symfony/browser-kit`'s `HttpBrowser` uses it to parse fetched pages. `Crawler::addXmlContent()` sets `DOMDocument::$validateOnParse = true` before calling `loadXML()`. Setting `validateOnParse` re-enables libxml's DTD subset processing, including external entity resolution, even though `LIBXML_NONET` is passed. `LIBXML_NONET` blocks **network** fetches but not `file://` entities. An attacker-supplied XML document with a `SYSTEM "file:///etc/passwd"` entity is therefore expanded. ### Resolution The `Crawler::addXmlContent` method does not set the `validateOnParse` flag anymore. The patch for this issue is available [here](https://github.com/symfony/symfony/commit/eea5fd7488cbdc241da4ce242344b7d9a3ecdf3d) for branch 5.4. ### Credits Symfony would like to thank Claude Mythos Preview (via Project Glasswing) for reporting the issue and providing the fix.
How to fix CVE-2026-45071
No fixed version has been published yet. Mitigate by removing the affected package or applying upstream guidance from the references below.
- —no fix listed
Is CVE-2026-45071 being exploited?
Low — EPSS is 0.5%, meaning exploitation activity has not been observed at scale.
Affected packages (1)
- from 0
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 3.1 | HIGH7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N |