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 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.
What this means
- Exposure
- Exploitable from the adjacent network and with a privileged account — but only if a user opens booby-trapped content.
- Impact
- An attacker can read sensitive data, modify or destroy data and take the service offline.
- Weakness
- Attacker-supplied script runs in other users’ browsers (cross-site scripting).
- Likelihood
- Its EPSS score stays low: nothing points to imminent exploitation, which is no reason to leave it unpatched.
What to doFold into the next patch cycle.
Read automatically from the CVSS vector, the weakness type (CWE) and the EPSS score. The technical description above remains the one published by NIST.