CVE-2026-19505
RDK-B WebUI improper cryptographic signature verification vulnerability
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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Exploit likelihood
What each source reports
CVE List Score used
RDK-B WebUI improper cryptographic signature verification vulnerability
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.
- Record
CVE-2026-19505- CVSS 3.1
- 9.8 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-347
- Updated
- 2026-11-02
EUVDEUVD-2026-62711
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.
- Record
EUVD-2026-62711- CVSS 3.1
- 9.8 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-j328-w5qv-gh82
Improper cryptographic signature verification in `jst_functions.c` in RDK-B WebUI `rdkb-2025q4...
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.
- Record
GHSA-j328-w5qv-gh82- CVSS 3.1
- 9.8 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-347
- Updated
- 2026-11-02
NVD
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.
- Record
CVE-2026-19505- CVSS 3.1
- 9.8 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-347
- Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, NVD |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-19505 is a critical vulnerability (CVSS 9.8) in Rdk Rdk-b Webui, published August 19, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.51%, the 43rd percentile. No source names a fixed version.