CVE-2026-19505
Critical
Description
Improper cryptographic signature verification in `jst_functions.c` in RDK-B WebUI `rdkb-2025q4-kirkstone.04.10.26` allows a remote attacker to bypass authentication and obtain administrative access via a forged JWT containing an invalid RSA signature.
SeverityCritical
CVSS9.8
Exploit probability—
ProductRDK-B WebUI
PublishedAug 19, 2026
First seenAug 19, 2026
Weakness typeCWE-347CWE-347
How to fix
Sources list no fixed version or patch link for this vulnerability.
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| RDK RDK-B WebUI | rdkb-2025q4-kirkstone | — |
Check your version
Choose the product and enter the version you run to see whether it falls in the affected range.
In the Intelligence 360 plan
Attack Surface Management
See the assets tied to your domains, the technologies they run and known vulnerabilities in one list.