CVE-2026-19505CWE-347

CVE-2026-19505

Critical · published August 20, 2026

CVSS v3.1
9.8
EPSS
0%
Percentile
29.3
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v3.1
9.8 · CRITICAL
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CVSS v4.0
Not supplied
EPSS
0.00366 · 29.3th percentile
Weakness
CWE-347 · Improper Verification of Cryptographic Signature
Published
2026-08-20T00:17Z
References (2)
https://developer.rdkcentral.com/documentation/documentation/rdk_broadband_documentation/components/webui/ · [email protected]https://whitehats.pwr.edu.pl//blog/2026-08-19-multiple-vulnerabilities-in-rdkb/ · [email protected]
EPSS history
Timeline
  • 19 AUG 19:27Z
    RDK-B WebUI improper cryptographic signature verification vulnerability
    cvelistv5