CVE-2026-7808
CRITICALCVE-2026-7808 is a critical-severity (CVSS 9.8) Improper Input Validation vulnerability. O3 Security confirms whether CVE-2026-7808 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
justhtml before 1.16.0 contains multiple HTML sanitization bypass issues that can allow active/dangerous content (e.g., script or style) to survive sanitization, potentially leading…
Description
justhtml before 1.16.0 contains multiple HTML sanitization bypass issues that can allow active/dangerous content (e.g., script or style) to survive sanitization, potentially leading to cross-site scripting. The issues primarily affect advanced usage rather than the default JustHTML(..., sanitize=True) path for ordinary parsed HTML: mutating or reusing sanitization policy objects (including exported defaults) could weaken later sanitization; programmatic DOM input to sanitize()/sanitize_dom() could miss mixed-case tag names (e.g., ScRiPt, StYlE); crafted programmatic doctype names could serialize into active markup; and custom policies preserving SVG or MathML could allow animation elements, presentation attributes with external url(...) references, or DOM trees mislabeled as namespace="html" to bypass foreign-content checks. Fixed in 1.16.0.
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-2026-7808 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-2026-7808 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-2026-7808. 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-2026-7808 in your dependencies?
O3 detects CVE-2026-7808 across dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.