What is CVE-2026-21409?

CVE-2026-21409 is a medium-severity vulnerability in Ricoh Company, Ltd. Streamline Nx, classified under Authorization Bypass Through User-Controlled Key. CVSS score: 5.9/10. Published 2026-01-09.

How severe is CVE-2026-21409?

Medium severity. CVSS v3 base score is 5.9 out of 10.

Auth bypass in Ricoh Company, Ltd. Streamline Nx

CVE-2026-21409

Improper authorization vulnerability exists in RICOH Streamline NX 3.5.1 to 24R3. If a man-in-the-middle attack is conducted on the communication between the affected product and its user, and some crafted request is processed by the product, the user's registration information and/or OIDC (OpenID Connect) tokens may be retrieved.

Vulnerability class: IDOR (Insecure Direct Object Reference)

EPSS: 0.003 (25.1th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 5.9 (Medium). Vector: CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N.

Affected products

Ricoh Company, Ltd. Streamline Nx — versions 3.5.1 to 24R3

Weakness classification (CWE)

CWE-639 — Authorization Bypass Through User-Controlled Key

References

Frequently asked questions

What is CVE-2026-21409?: CVE-2026-21409 is a medium-severity vulnerability in Ricoh Company, Ltd. Streamline Nx, classified under Authorization Bypass Through User-Controlled Key. CVSS score: 5.9/10. Published 2026-01-09.
How severe is CVE-2026-21409?: Medium severity. CVSS v3 base score is 5.9 out of 10.