CVE-2026-47666 is a high-severity (CVSS 7.6) Cross-site Scripting (XSS) vulnerability. O3 Security confirms whether CVE-2026-47666 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
Penpot is an open-source design and prototyping platform. In versions up to and including 2.14.3, Penpot is vulnerable to stored cross-site scripting through custom font family names,…
Exploitation Status
Proof-of-concept exploit code exists
- CISA’s SSVC triage found public proof-of-concept exploit code for this CVE, though no confirmed active exploitation.
Exploitation and automatability from CISA’s SSVC triage for CVE-2026-47666.
Description
Penpot is an open-source design and prototyping platform. In versions up to and including 2.14.3, Penpot is vulnerable to stored cross-site scripting through custom font family names, which are interpolated into a @font-face CSS rule and injected into the page as HTML without sanitization. Because the backend accepts an arbitrary font-family string and the frontend writes the resulting style through innerHTML, a name containing markup such as a closing style tag followed by a script can break out of the style element and execute JavaScript on the Penpot origin. The attack is passive: any team member who opens a file referencing the malicious font triggers script execution simply by rendering the page, allowing theft of session cookies, actions performed as the victim, and access to their files and projects. This issue is fixed in version 2.15.3.
Detection & mitigation playbook
VulnerabilityDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for the affected component. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Remediation status
No patched version of the affected component has shipped for CVE-2026-47666 yet. Where your build allows, override or pin the dependency away from the vulnerable range, and apply any maintainer-recommended mitigation.
Mitigate without a patch
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether CVE-2026-47666 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to CVE-2026-47666. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2026-47666 in your dependencies?
O3 detects CVE-2026-47666 across dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.