{"id":"CVE-2026-71502","url":"https://www.cyber-defence.io/tools/cve/CVE-2026-71502","generatedAt":"2026-10-28T00:07:59.736Z","title":"CTI-Transmute contains a stored cross-site scripting vulnerability caused by insufficient neutralization of Vue template expression delimiters in server-rendered user-controlled data.","description":"CTI-Transmute contains a stored cross-site scripting vulnerability caused by insufficient neutralization of Vue template expression delimiters in server-rendered user-controlled data.\n\nAn unauthenticated attacker can create a public conversion whose name or description contains a malicious Vue expression using the application's configured [[ ... ]] delimiters. User profile names may provide an additional injection vector. Although Jinja HTML escaping is applied, the resulting value is subsequently included in a DOM region compiled by Vue.\n\nVue interprets the attacker-controlled value as a template expression rather than ordinary text. By accessing the JavaScript Function constructor from within the expression, an attacker can execute arbitrary JavaScript in the security context of the CTI-Transmute origin. The application's nonce-based Content Security Policy does not prevent exploitation because the Vue runtime compiler requires the unsafe-eval policy exception.\n\nThe malicious payload is stored by the application and executed whenever another user opens an affected page, such as the public conversion detail page. The victim may be a normal user or an administrator. Successful exploitation could allow the attacker to:\n\n  *  Access data available to the victim through the application.\n  *  Extract API keys, tokens, or other sensitive information exposed to the page.\n  *  Perform authenticated actions using the victim's session.\n  *  Modify conversions or other application data.\n  *  Escalate the impact by targeting an administrator.\n\n\nA demonstrated payload can use [].constructor.constructor(...) to obtain the JavaScript Function constructor and execute arbitrary code. The regression tests also show that a short first-stage payload could retrieve an uncapped conversion description and evaluate a larger second-stage payload.\n\nThe patch addresses the vulnerability by registering a global Jinja finalize hook that inserts a zero-width Unicode word joiner inside every Vue delimiter found in server-rendered values. This prevents Vue from recognizing the values as template expressions while preserving their visible representation.","published":"2026-08-08T22:16:34.000Z","lastModified":"2026-10-24T15:10:00.000Z","status":"Deferred","sourceIdentifier":"5a6e4751-2f3f-4070-9419-94fb35b644e8","cvss":{"version":"4.0","score":5.1,"severity":"MEDIUM","vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M"},"cwe":["CWE-79","CWE-1336"],"affected":[],"epss":{"score":0.00738,"percentile":0.54245,"date":"2026-10-26","history":[]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"low","text":"Lower severity and a low EPSS score (0.74%). Track it; it rarely justifies an emergency change on its own."},"changes":[],"references":[{"url":"https://github.com/MISP/cti-transmute/commit/4f43c9181a00262bec2a6dfbc9ff9c50d534e918","source":"5a6e4751-2f3f-4070-9419-94fb35b644e8"},{"url":"https://github.com/MISP/cti-transmute/commit/522fa8ff8223b12a6128ea3fc2344a77b7b9108d","source":"5a6e4751-2f3f-4070-9419-94fb35b644e8"},{"url":"https://github.com/MISP/cti-transmute/commit/ad8bf2b8031491cefb552314ef7ff6f4148ca95a","source":"5a6e4751-2f3f-4070-9419-94fb35b644e8"},{"url":"https://github.com/MISP/cti-transmute/commit/ecfdaef63860a071c6f07afd30156ca77a77ad2b","source":"5a6e4751-2f3f-4070-9419-94fb35b644e8"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-71502","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}