CVE-2026-21409
Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.
NVD · uneditedImproper 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.
Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.
dbcve analysis · moderate confidenceRICOH Streamline NX versions 3.5.1 through 24R3 contain an improper authorization vulnerability allowing man-in-the-middle attackers to intercept and retrieve user registration information and OIDC tokens. The vulnerability stems from insufficient authorization controls during the authentication flow when an attacker can position themselves between the client and server.
Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.
CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.
From the vector- Attack vector
- Network
- Complexity
- High
- Privileges
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- None
- Availability
- None
CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N
Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.
dbcve checksWork through these to decide whether this CVE applies to you.
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Identify RICOH Streamline NX installation and versionLocate the Streamline NX installation directory or check system information for the installed version number. Common locations include the program files directory or the application configuration files where version metadata is stored.Affected if The installed version falls within 3.5.1 through 24R3 inclusive.
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Confirm OIDC authentication is configuredExamine the Streamline NX authentication configuration files or admin console settings to determine if OpenID Connect (OIDC) authentication is enabled for user login.Affected if OIDC authentication is enabled and the version is in the affected range.
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Verify TLS certificate configuration for authentication endpointsInspect the TLS/SSL configuration for the authentication endpoints. Check if mutual TLS (client certificate validation) or certificate pinning is configured for OIDC communication channels.Affected if Mutual TLS or certificate pinning is NOT configured and the version is in the affected range, indicating vulnerability to MITM interception.
The environment is affected if RICOH Streamline NX version 3.5.1 through 24R3 is installed with OIDC authentication enabled and without mutual TLS or certificate pinning protecting the authentication flow.
Generated from the published advisory. Verify against your own configuration.
Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.
From vendor dataImplement proper authorization validation and ensure all OIDC authentication flows use certificate pinning or mutual TLS to prevent MITM attacks. Update to a patched version if available.
- Consultation4.0 h
- Implementation12.0 h
- Testing6.0 h
- Review / QA3.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $7,040.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2026-21409 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.
References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.
Primary sourcesPractitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-2026-21409 in production — separate from our analysis above.
The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.
- The version that genuinely resolved it — not the one the vendor claimed
- A config change or rule that shut the vector down
- A gotcha in the upgrade path that cost you an afternoon
No notes yet
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- Version or environment caveats, and links to real fixes
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