{"id":"CVE-2026-125341","kind":"vulnerability","aliases":["CVE-2026-125341","GHSA-7mpf-4465-7fc2"],"related":[],"title":"Winter: Stored XSS through Backend List widget image columns","description":"### Impact\n\n`Backend\\Widgets\\Lists::evalImageTypeValue()` interpolated the resolved image URL into a single-quoted `src` attribute without escaping it. Where a list column of type [`image`](https://wintercms.com/docs/v1.2/docs/backend/lists#image) rendered an attacker-influenced value, that value could break out of the attribute and inject arbitrary attributes — including event handlers — into the backend list, executing in the session of whichever backend user viewed it.\n\nWinter core ships no `image` list column, so a default installation is unaffected. Exploitation requires a plugin that renders attacker-influenced values through one.\n\nThe supported [image sources](https://wintercms.com/docs/v1.2/docs/services/image-resizing#available-sources) are plugins, themes, the Media Library, the uploads directory, and `Attach\\File` models; an arbitrary external URL is not among them. `ImageResizer::filterGetUrl()` returns the value it was given when it cannot resolve an image, however, so an unsupported value reached the attribute verbatim rather than being rejected.\n\nAs with previous issues of this kind the severity is limited: an attacker must already be able to store the value, and a backend user must then open the affected list. Note that validating a stored URL was not necessarily sufficient — a payload can survive `filter_var($url, FILTER_VALIDATE_URL)`, since `/` is valid both in a URL path and after a quoted HTML attribute value.\n\n### Patches\n\n`evalImageTypeValue()` now escapes the image URL, along with the width and height taken from the column configuration, before interpolating them into the tag.\n\nThis security issue has been fixed as of **v1.2.14** (commit [`0941c9816181095fe35d58e78e6d0c4a49238967`](https://github.com/wintercms/winter/commit/0941c9816181095fe35d58e78e6d0c4a49238967)).\n\n### Workarounds\n\nApply the commit above to `modules/backend/widgets/Lists.php` manually if you are unable to upgrade to v1.2.14.\n\n### References\n\n- https://github.com/wintercms/winter/security/advisories/GHSA-43w4-4j3c-jx29\n- https://github.com/wintercms/winter/commit/0941c9816181095fe35d58e78e6d0c4a49238967\n\n\nCredit to Seungyeon Park ([@sy460129](https://github.com/sy460129)) for reporting the issue.\n\n### For more information\n\nIf you have any questions or comments about this advisory:\n- Email us at [hello@wintercms.com](mailto:hello@wintercms.com)","summary":"The Winter CMS backend list widget inserted an image URL into an HTML attribute without escaping it, so a crafted stored value can break out and add script event handlers. The script then runs in the session of any backend user who views that list.","severity":"low","cvss":2.0,"epss":null,"exploited":false,"exploited_at":null,"products":[{"name":"winter/wn-backend-module","fixed":["1.2.14"],"affected":">= 1.1.0, < 1.2.14","ecosystem":"composer"}],"ecosystems":["composer"],"tags":["cwe-79","package","php","self-hosted","winter-cms"],"not_affected_if":["auth-required","default-config","no-image-list-column"],"how_to_check":"- Check the version of `composer:winter/wn-backend-module` in `composer.lock`; affected versions are `>= 1.1.0, < 1.2.14`.\n- Search plugins for list column definitions with `type: image` that show user-supplied values.","fix":"- `winter/wn-backend-module`: upgrade to `1.2.14`\n- If upgrading is not possible, the advisory says to apply the fix commit to `modules/backend/widgets/Lists.php` manually.","status":"open","published_at":"2026-08-20T18:44:41+00:00","first_seen_at":"2026-11-10T20:10:42+00:00","triaged_at":"2026-11-10T20:12:35+00:00","updated_at":"2026-11-10T20:12:35+00:00","category":"package","confidence":0.8,"triage":{"at":"2026-11-10T20:12:35Z","model":"claude-haiku-5-5","output":{"fix":"- `winter/wn-backend-module`: upgrade to `1.2.14`\n- If upgrading is not possible, the advisory says to apply the fix commit to `modules/backend/widgets/Lists.php` manually.","reach":"internet","title":"Winter CMS: stored XSS in backend list image columns","impact":"medium","summary":"The Winter CMS backend list widget inserted an image URL into an HTML attribute without escaping it, so a crafted stored value can break out and add script event handlers. The script then runs in the session of any backend user who views that list.","audience":"businesses","category":"package","nicknames":[],"who_cares":["winter-cms","php","self-hosted"],"confidence":0.8,"fix_status":"available","needs_auth":"yes","worst_case":"script runs in a backend user's session when they view a list","analyst_note":"","how_to_check":"- Check the version of `composer:winter/wn-backend-module` in `composer.lock`; affected versions are `>= 1.1.0, < 1.2.14`.\n- Search plugins for list column definitions with `type: image` that show user-supplied values.","plain_action":"","product_name":"","needs_analyst":false,"not_affected_if":["default-config","no-image-list-column","auth-required"],"who_is_affected":"Only sites running Winter CMS 1.1.0 up to 1.2.13 that have a plugin rendering attacker-influenced values through an `image` list column. Winter core ships no such column, so a default installation is not affected. An attacker must already be able to store the value, and a backend user must open the affected list.","user_interaction":"yes","product_ecosystem":"","needs_special_setup":"yes","severity_if_unknown":"low"},"cost_usd":0.000827,"input_tokens":5425,"output_tokens":569,"severity_before":"low"},"analyst_status":null,"analyst_note":null,"search":"'-125341':12A,21A '-2026':11A,20A '-7':17A '-79':24B '/docs/v1.2/docs/backend/lists#image)':107C '/docs/v1.2/docs/services/image-resizing#available-sources)':174C '/sy460129))':357C '/wintercms/winter/commit/0941c9816181095fe35d58e78e6d0c4a49238967':349C '/wintercms/winter/commit/0941c9816181095fe35d58e78e6d0c4a49238967)).':326C '/wintercms/winter/security/advisories/ghsa-43w4-4j3c-jx29':346C '0941c9816181095fe35d58e78e6d0c4a49238967':323C '4465':16A '7mpf':15A 'abl':239C 'add':59B 'advisori':374C 'affect':252C 'along':296C 'alreadi':237C 'among':194C 'appli':328C 'arbitrari':124C,189C 'attach':185C 'attack':111C,163C,235C 'attacker-influenc':110C,162C 'attribut':46B,94C,121C,125C,217C,287C 'backend':5A,36B,72B,79C,131C,139C,246C 'break':56B,117C 'cannot':206C 'cms':32B,35B 'column':9A,101C,149C,305C 'comment':371C 'commit':322C,330C 'configur':306C 'core':144C 'could':116C 'craft':52B 'credit':350C 'cve':10A,19A 'cwe':23B 'default':152C 'directori':183C 'email':375C 'escap':48B,96C,292C 'evalimagetypevalu':82C,290C 'event':61B,127C 'execut':133C 'exploit':156C 'extern':190C 'fc2':18A 'file':186C 'filter':268C,271C 'filtergeturl':197C 'fix':318C 'ghsa':14A 'ghsa-7mpf':13A 'github.com':325C,345C,348C,356C 'github.com/sy460129))':355C 'github.com/wintercms/winter/commit/0941c9816181095fe35d58e78e6d0c4a49238967':347C 'github.com/wintercms/winter/commit/0941c9816181095fe35d58e78e6d0c4a49238967)).':324C 'github.com/wintercms/winter/security/advisories/ghsa-43w4-4j3c-jx29':344C 'given':203C 'handler':62B,128C 'height':301C 'hello@wintercms.com':378C,380C 'host':29B 'howev':210C 'html':45B,286C 'imag':8A,41B,86C,104C,147C,170C,209C,294C 'imageres':196C 'impact':78C 'includ':126C 'influenc':112C,164C 'inform':364C 'inject':123C 'insert':39B 'instal':153C 'interpol':83C,308C 'issu':226C,315C,361C 'kind':229C 'librari':180C 'limit':233C 'list':6A,37B,77B,81C,100C,132C,148C,253C 'mailto':379C 'manual':334C 'media':179C 'model':187C 'modules/backend/widgets/lists.php':333C 'must':236C,248C 'necessarili':262C 'note':254C 'one':167C 'open':250C 'packag':25B 'park':353C 'patch':289C 'path':281C 'payload':265C 'php':26B 'plugin':159C,176C 'previous':225C 'question':369C 'quot':92C,285C 'rather':219C 'reach':215C 'refer':343C 'reject':222C 'render':108C,161C 'report':359C 'requir':157C 'resolv':85C,207C 'return':198C 'run':66B 'script':60B,64B 'secur':314C 'self':28B 'self-host':27B 'session':69B,136C 'seungyeon':352C 'sever':231C 'ship':145C 'sinc':274C 'singl':91C 'single-quot':90C 'sourc':171C 'src':93C 'store':2A,53B,241C,258C 'suffici':263C 'support':169C 'surviv':267C 'sy460129':354C 'tag':312C 'taken':302C 'theme':177C 'type':103C 'unabl':338C 'unaffect':155C 'unsupport':213C 'upgrad':340C 'upload':182C 'url':42B,87C,191C,259C,270C,273C,280C,295C 'us':376C 'user':73B,140C,247C 'v1.2.14':321C,342C 'valid':256C,272C,276C 'valu':54B,113C,115C,165C,200C,214C,243C,288C 'var':269C 'verbatim':218C 'view':75B,141C 'whichev':138C 'widget':7A,38B,80C 'width':299C 'winter':1A,31B,34B,143C 'winter-cm':30B 'winter/wn-backend-module':22A 'wintercms.com':106C,173C 'wintercms.com/docs/v1.2/docs/backend/lists#image)':105C 'wintercms.com/docs/v1.2/docs/services/image-resizing#available-sources)':172C 'without':47B,95C 'workaround':327C 'xss':3A","nicknames":[],"mitigations":[],"who_affected":"Only sites running Winter CMS 1.1.0 up to 1.2.13 that have a plugin rendering attacker-influenced values through an `image` list column. Winter core ships no such column, so a default installation is not affected. An attacker must already be able to store the value, and a backend user must open the affected list.","tier":"C","verified":{},"analyst_revisit_at":null,"fix_status":"available","audience":"businesses","plain_action":null,"pkeys":["winterwnbackendmodule"],"ptokens":["backend","module","winter","wn"],"labels":["composer","cwe79","low","package","php","selfhosted","wintercms"],"campaign_type":null,"search_a":"'-125341':12A,21A '-2026':11A,20A '-7':17A '4465':16A '7mpf':15A 'backend':5A 'column':9A 'cve':10A,19A 'fc2':18A 'ghsa':14A 'ghsa-7mpf':13A 'imag':8A 'list':6A 'store':2A 'widget':7A 'winter':1A 'winter/wn-backend-module':22A 'xss':3A","search_b":"'-79':24B 'add':59B 'attribut':46B 'backend':36B,72B 'break':56B 'cms':32B,35B 'craft':52B 'cwe':23B 'escap':48B 'event':61B 'handler':62B 'host':29B 'html':45B 'imag':41B 'insert':39B 'list':37B,77B 'packag':25B 'php':26B 'run':66B 'script':60B,64B 'self':28B 'self-host':27B 'session':69B 'store':53B 'url':42B 'user':73B 'valu':54B 'view':75B 'widget':38B 'winter':31B,34B 'winter-cm':30B 'without':47B","search_c":"'/docs/v1.2/docs/backend/lists#image)':107C '/docs/v1.2/docs/services/image-resizing#available-sources)':174C '/sy460129))':357C '/wintercms/winter/commit/0941c9816181095fe35d58e78e6d0c4a49238967':349C '/wintercms/winter/commit/0941c9816181095fe35d58e78e6d0c4a49238967)).':326C '/wintercms/winter/security/advisories/ghsa-43w4-4j3c-jx29':346C '0941c9816181095fe35d58e78e6d0c4a49238967':323C 'abl':239C 'advisori':374C 'affect':252C 'along':296C 'alreadi':237C 'among':194C 'appli':328C 'arbitrari':124C,189C 'attach':185C 'attack':111C,163C,235C 'attacker-influenc':110C,162C 'attribut':94C,121C,125C,217C,287C 'backend':79C,131C,139C,246C 'break':117C 'cannot':206C 'column':101C,149C,305C 'comment':371C 'commit':322C,330C 'configur':306C 'core':144C 'could':116C 'credit':350C 'default':152C 'directori':183C 'email':375C 'escap':96C,292C 'evalimagetypevalu':82C,290C 'event':127C 'execut':133C 'exploit':156C 'extern':190C 'file':186C 'filter':268C,271C 'filtergeturl':197C 'fix':318C 'github.com':325C,345C,348C,356C 'github.com/sy460129))':355C 'github.com/wintercms/winter/commit/0941c9816181095fe35d58e78e6d0c4a49238967':347C 'github.com/wintercms/winter/commit/0941c9816181095fe35d58e78e6d0c4a49238967)).':324C 'github.com/wintercms/winter/security/advisories/ghsa-43w4-4j3c-jx29':344C 'given':203C 'handler':128C 'height':301C 'hello@wintercms.com':378C,380C 'howev':210C 'html':286C 'imag':86C,104C,147C,170C,209C,294C 'imageres':196C 'impact':78C 'includ':126C 'influenc':112C,164C 'inform':364C 'inject':123C 'instal':153C 'interpol':83C,308C 'issu':226C,315C,361C 'kind':229C 'librari':180C 'limit':233C 'list':81C,100C,132C,148C,253C 'mailto':379C 'manual':334C 'media':179C 'model':187C 'modules/backend/widgets/lists.php':333C 'must':236C,248C 'necessarili':262C 'note':254C 'one':167C 'open':250C 'park':353C 'patch':289C 'path':281C 'payload':265C 'plugin':159C,176C 'previous':225C 'question':369C 'quot':92C,285C 'rather':219C 'reach':215C 'refer':343C 'reject':222C 'render':108C,161C 'report':359C 'requir':157C 'resolv':85C,207C 'return':198C 'secur':314C 'session':136C 'seungyeon':352C 'sever':231C 'ship':145C 'sinc':274C 'singl':91C 'single-quot':90C 'sourc':171C 'src':93C 'store':241C,258C 'suffici':263C 'support':169C 'surviv':267C 'sy460129':354C 'tag':312C 'taken':302C 'theme':177C 'type':103C 'unabl':338C 'unaffect':155C 'unsupport':213C 'upgrad':340C 'upload':182C 'url':87C,191C,259C,270C,273C,280C,295C 'us':376C 'user':140C,247C 'v1.2.14':321C,342C 'valid':256C,272C,276C 'valu':113C,115C,165C,200C,214C,243C,288C 'var':269C 'verbatim':218C 'view':141C 'whichev':138C 'widget':80C 'width':299C 'winter':143C 'wintercms.com':106C,173C 'wintercms.com/docs/v1.2/docs/backend/lists#image)':105C 'wintercms.com/docs/v1.2/docs/services/image-resizing#available-sources)':172C 'without':95C 'workaround':327C","cause_entry":null,"cause_path":null,"disclosures_checked_at":null,"first_public_at":"2026-08-19T22:06:56+00:00","kev":null,"cvss_vector":"CVSS:3.1/AV:N/AC:H/PR:H/UI:R/S:U/C:N/I:L/A:N","cvss_by":"GitHub","poc_count":0,"sources":[{"source":"ghsa","external_id":"GHSA-7mpf-4465-7fc2","url":"https://github.com/advisories/GHSA-7mpf-4465-7fc2","severity":"low","published_at":"2026-08-20T18:44:41+00:00","modified_at":"2026-11-10T20:08:40+00:00","first_seen_at":"2026-11-10T20:10:42+00:00","fetched_at":"2026-11-10T20:56:29+00:00","note":null},{"source":"nvd","external_id":"CVE-2026-125341","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-125341","severity":null,"published_at":"2026-11-10T20:19:08+00:00","modified_at":"2026-11-10T20:19:08+00:00","first_seen_at":"2026-11-10T20:46:04+00:00","fetched_at":"2026-11-10T20:46:17+00:00","note":null}],"documents":[{"id":117785,"url":"https://api.github.com/repos/wintercms/winter/security-advisories/GHSA-7mpf-4465-7fc2","title":"Maintainer's advisory: api.github.com","kind":"vendor","source":"ghsa","publisher":"vendor","text":null,"published_at":null,"relation":"advisory","confidence":null,"note":"Maintainer's advisory: api.github.com"},{"id":117786,"url":"https://github.com/wintercms/winter/security/advisories/GHSA-7mpf-4465-7fc2","title":"Maintainer's advisory: github.com","kind":"vendor","source":"ghsa","publisher":"vendor","text":null,"published_at":"2026-08-19T22:06:56+00:00","relation":"advisory","confidence":null,"note":"Maintainer's advisory: github.com"},{"id":117787,"url":"https://github.com/wintercms/winter/commit/0941c9816181095fe35d58e78e6d0c4a49238967","title":"Patch: github.com","kind":"other","source":"ghsa","publisher":"vendor","text":null,"published_at":null,"relation":"fix","confidence":null,"note":"Patch: github.com"},{"id":117757,"url":"https://github.com/wintercms/winter/releases/tag/v1.2.14","title":"Release: github.com","kind":"release","source":"ghsa","publisher":"vendor","text":null,"published_at":null,"relation":"fix","confidence":null,"note":"Release: github.com"}],"disclosures":[],"exploit_sources":[],"notice":"Free to read, with fair use of about 60 pages a minute. For higher limits or API access: sales@infrastack.ai"}