CVE-2026-19505
CriticalCVSS 9.8Exploitation Probability (EPSS)
Low risk32th percentile - higher than 32% of all known CVEs
Summary
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.
Risk Assessment
An attacker can gain full administrative control over the system, posing a critical security threat.
Recommendation
Immediately update RDK-B WebUI and enforce proper JWT signature verification.
Other vulnerabilities in RDK-B WebUI
See all- CVE-2026-19508Critical
Heap-based buffer overflow in the multipart form-data parser in `jst_post.c` in RDK-B WebUI `rdkb-2025q4-kirkstone.04.10.26` allows a remote unauthenticated attacker to cause memory corruption and denial of service, and potentially execute arbitrary code, via a crafted multipart/form-data request.
- CVE-2026-19509Medium
Improper input validation in `ajaxSet_wireless_network_configuration.jst` in RDK-B WebUI `rdkb-2025q4-kirkstone.04.10.26` allows an authenticated attacker to cause denial of service via a crafted `ssid_number` parameter.
- CVE-2026-19507High
Uncontrolled resource consumption in `check.jst` in RDK-B WebUI `rdkb-2025q4-kirkstone.04.10.26` allows a remote unauthenticated attacker to cause denial of service via excessively large password values.
- CVE-2026-19506High
Race condition in `check.jst` in RDK-B WebUI `rdkb-2025q4-kirkstone.04.10.26` allows a remote attacker to gain unauthorized access via concurrent authentication requests that exploit shared authentication state.
Original NVD description (English source)
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.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS