CVE-2026-8699
A stored Cross-Site Scripting (XSS) vulnerability has been identified in the web-based management interface of Archer C5 v6.8 routers, due to insufficient server-side validation and…
Description
A stored Cross-Site Scripting (XSS) vulnerability has been identified in the web-based management interface of Archer C5 v6.8 routers, due to insufficient server-side validation and lack of proper output encoding of user-controlled input in a certain field. An attacker with administrative privileges can inject crafted HTML or JS payloads into the affected field. The payload is stored and later executed when the affected page is rendered in an administrator's browser.Successful exploitation allows execution of arbitrary JavaScript in an admin's browser, potentially leading to session hijacking and unauthorized access to router configuration, possibly resulting in exposure of sensitive data and modification of device settings.
The vulnerability affects ISP-managed firmware variants of the product. Remediation is coordinated through service providers.
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-2026-8699 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-2026-8699 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-2026-8699. 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-2026-8699 in your dependencies?
O3 detects CVE-2026-8699 across dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.