{"id":"CVE-2026-49216","title":"symfony/ux-autocomplete: XSS via unescaped AJAX response data","summary":"symfony/ux-autocomplete: XSS via unescaped AJAX response data","severity":"medium","cwe":["CWE-79"],"vendor":"symfony","product":"symfony/ux-autocomplete","affected":["symfony/ux-autocomplete >= 2.2.0, < 2.36.0","symfony/ux-autocomplete >= 3.0.0, < 3.1.0"],"patched":["symfony/ux-autocomplete 2.36.0","symfony/ux-autocomplete 3.1.0"],"published":"2026-06-19","updated":"2026-06-19","source":"GHSA","sourceUrl":"https://github.com/advisories/GHSA-mwqm-4fw3-cjvr","references":[{"url":"https://github.com/symfony/ux/security/advisories/GHSA-mwqm-4fw3-cjvr"},{"url":"https://github.com/symfony/ux/commit/842ae54bc74de389299f975f01aafae272cb0019"},{"url":"https://github.com/FriendsOfPHP/security-advisories/blob/master/symfony/ux-autocomplete/CVE-2026-49216.yaml"},{"url":"https://github.com/advisories/GHSA-mwqm-4fw3-cjvr"}],"tags":["ghsa","composer"],"ingestedAt":"2026-06-22T15:52:21.061Z","ecosystem":"composer","epss":0.00312,"epssPercentile":0.2426,"slug":"CVE-2026-49216","body":"## Overview\n\n### Description\n\nThe Stimulus controller shipped with `symfony/ux-autocomplete` renders AJAX response items into the dropdown by interpolating the `text` field directly into HTML template literals (`<div>${item[labelField]}</div>`) inside `_createAutocompleteWithRemoteData()`. The value is parsed as HTML rather than text, so any markup contained in the AJAX response is executed by the browser.\n\nWhen the dropdown values are derived from user-supplied content, an attacker can craft a string that triggers stored XSS in the browser of any other user who later opens a page containing an autocomplete widget backed by the same data.\n\n### Resolution\n\nThe `option` and `item` renderers used in `_createAutocompleteWithRemoteData()` now use TomSelect's `escape` helper to HTML-escape the value by default. Endpoints that legitimately return HTML (for example, to highlight the search term) can opt back in to the previous behavior by setting `options_as_html: true`. The `AutocompleteChoiceTypeExtension` normalizer that previously forced `options_as_html=false` when `autocomplete_url` was set has been dropped so the opt-in is reachable from the form layer.\n\nThe patch for this issue is available [here](https://github.com/symfony/ux/commit/842ae54bc74de389299f975f01aafae272cb0019) for branch 2.x (and forward-ported to 3.x).\n\n### Credits\n\nSymfony would like to thank Alex Ashkov for reporting the issue and Hugo Alliaume for providing the fix.\n\n## Affected packages\n\n- `symfony/ux-autocomplete >= 2.2.0, < 2.36.0`\n- `symfony/ux-autocomplete >= 3.0.0, < 3.1.0`\n\n## Remediation\n\nUpgrade to a patched release:\n\n- `symfony/ux-autocomplete 2.36.0`\n- `symfony/ux-autocomplete 3.1.0`","depth":"sunlit","depthScore":28,"depthScoreParts":{"impact":27.5,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}