by Kastro
Paper/Archive/CVE-2026-19505

CVE-2026-19505

RDK RDK-B WebUI — RDK-B WebUI improper cryptographic signature verification vulnerability

EPSS 0.5%CVSS 9.8
critical.is priorityof 100
38
CVSS 9.8 (ADP)9.8 / 10 × 3029.4Not in CISA KEV+300.0EPSS percentile 43.6.436 × 208.7No public exploit+100.0SSVC exploitation: none+100.0
Description · from the CVE record

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.

Affected

ProductAffectedFixed inSource
RDK-B WebUIrdkb-2025q4-kirkstone–CNA

Scores by source

CISA ADP9.8CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CISA ADPSSVCExploitation: none · Automatable: yes · Technical impact: total

References

refwhitehats.pwr.edu.pl//blog/2026-08-19-multiple-vulnerabilities-in-rdkbrefdeveloper.rdkcentral.com/documentation/documentation/rdk_broadband_documentation/components/webui