CVE-2026-61453
CVE-2026-61453 is a Cross-site Scripting (XSS) vulnerability in getgrav/grav. O3 Security confirms whether CVE-2026-61453 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
Grav before 2.0.1 XSS via Twig String Concatenation
Real-World Exposure
getgrav/gravReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Packagist packages — download data is not available via public APIs for these ecosystems.
Description
Grav v2.0.0 contains a cross-site scripting vulnerability (fixed in 2.0.1). The XSS blueprint validator (Security::detectXss()) runs on raw page content before Twig processing. When Twig content processing is enabled (twig_content.process_enabled: true), an attacker with page-write API permission can use Twig's string concatenation operator (~) to dynamically construct event handler names, dangerous tag names, or dangerous protocols at render time (e.g. {% set x = "on" ~ "error" %}). The validator sees only the harmless Twig expression and allows the content, but after Twig rendering the output (rendered via {{ page.content|raw }}) contains an active payload such as <img src=1 onerror=alert(1)>, executing arbitrary JavaScript in visitors' browsers.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐘Packagist | getgrav/grav | ≥ 2.0.0&&< 2.0.1 | 2.0.1 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for getgrav/grav. 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.
Fix
Update getgrav/grav to 2.0.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-61453 is resolved across your whole dependency graph.
Workarounds
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-2026-61453 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-2026-61453. 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-2026-61453 in your dependencies?
O3 detects CVE-2026-61453 across Packagist dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.