Quick answer
Direct answer
Risk scores
| CVSS metric | What it means |
|---|---|
| Attack vector (AV:N) | Network: reachable remotely |
| Attack complexity (AC:L) | Low complexity |
| Attack requirements (AT:N) | No attack requirements |
| Privileges required (PR:L) | Low privileges required |
| User interaction (UI:N) | No user interaction |
| Confidentiality (VC:H) | High confidentiality impact |
| Integrity (VI:H) | High integrity impact |
| Availability (VA:H) | High availability impact |
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
About Nerves-Hub Nerveshub
CVE-2026-28806 affects Nerves-Hub Nerveshub, a product from Nerves-Hub. Before acting, confirm where Nerves-Hub Nerveshub runs in your estate, who owns it and whether it is reachable from the internet, because exposure decides real risk more than the score alone.
What the flaw is
In plain terms: Improper Authorization vulnerability in nerves-hub nerves_hub_web allows cross-organization device control via device bulk actions and device update API. Missing authorization checks in the device bulk actions and device update API endpoints allow authenticated users to target devices belonging to other organizations and perform actions outside of their privilege level. An attacker can select devices outside of their organization by manipulating device identifiers and perform management actions on them, such as moving them to products they control. This may allow attackers to interfere with firmware updates, access device functionality exposed by the platform, or disrupt device connectivity. In environments where additional features such as remote console access are enabled, this could lead to full compromise of affected devices. This issue affects nerves_hub_web: from 1.0.0 before 2.4.0.
The weakness class is Improper Authorization. The software does not check whether a user is allowed to perform an action.
Based on its CVSS vector, the flaw can be reached over the network, needs some level of access, and needs no user interaction. Apply the vendor fix and confirm exposure on internet facing and business critical assets first.
Affected versions and timeline
| Field | Detail |
|---|---|
| Product | Nerves-Hub Nerveshub |
| Affected versions | Nerveshub from 1.0.0 before 2.4.0 |
| Published | Mar 10, 2026 |
| Last modified | Jun 17, 2026 |
| Added to CISA KEV | Not listed |
| Assigning CNA | 6b3ad84c-e1a6-4bf7-a703-f496b71e49db |
How to detect it
- Inventory every instance of Nerves-Hub Nerveshub and record the running version against the affected range above.
- Check external attack surface scans for internet facing instances of the component.
- Review logs on affected systems for unusual requests, errors or new processes around the vulnerable function.
- Confirm with an authenticated vulnerability scan once your scanner has a check for this CVE.
How to fix it
- Apply the fixed version of Nerves-Hub Nerveshub named in the vendor advisory.
- If patching must wait, restrict network access to the affected service and put it behind authentication or a web application firewall rule.
- Rescan after the change to prove the exposure is gone, then close the ticket.
CTEM action plan
| CTEM stage | What to do for this CVE |
|---|---|
| Scope | Add every business service that depends on Nerves-Hub Nerveshub to the current CTEM cycle. |
| Discover | Find all instances, including shadow and cloud deployments, and record versions and exposure. |
| Prioritize | Rank using EPSS and CVSS together with asset exposure and business impact. |
| Validate | Confirm the flaw is reachable and exploitable in your environment and that compensating controls work. |
| Mobilize | Assign the fix to the asset owner with a due date matched to the priority, then verify closure. |
CWE References
- CWE-285: Improper Authorization More CVEs with this weakness
- CWE-668: Exposure of Resource to Wrong Sphere More CVEs with this weakness
Technical References
Frequently asked questions
Related CVEs
NervesHub is a web service that allows users to manage over-the-air (OTA) firmware updates of devices in the field. A vulnerability present starting in version 1.0.0 and prior to version 2.3.0 allowed attackers to brute-force user API tokens due to the predictable format of previously issued tokens. Tokens included user-identifiable components and were not cryptographically secure, making them susceptible to guessing or enumeration. The vulnerability could have allowed unauthorized access to user accounts or API actions protected by these tokens. A fix is available in version 2.3.0 of NervesHub. This version introduces strong, cryptographically-random tokens using `:crypto.strong_rand_bytes/1`, hashing of tokens before database storage to prevent misuse even if the database is compromised, and context-aware token storage to distinguish between session and API tokens. There are no practical workarounds for this issue other than upgrading. In sensitive environments, as a temporary mitigation, firewalling access to the NervesHub server can help limit exposure until an upgrade is possible.
PolarLearn is a free and open-source learning program. In 0-PRERELEASE-16 and earlier, the group chat WebSocket at wss://polarlearn.nl/api/v1/ws can be used without logging in. An unauthenticated client can subscribe to any group chat by providing a group UUID, and can also send messages to any group. The server accepts the message and stores it in the group’s chatContent, so this is not just a visual spam issue.
In addInputMethodListener of com.android.server.inputmethod.InputMethodManagerService, there is a missing permission check. This could lead to local escalation of privilege with no additional execution privileges needed. User interaction is not needed for exploitation.
Improper authorization in Azure AI Foundry allows an unauthorized attacker to elevate privileges over a network.
Improper authorization in Microsoft Azure Kubernetes Service allows an unauthorized attacker to elevate privileges over a network.
FUXA is a web-based Process Visualization (SCADA/HMI/Dashboard) software. Prior to 1.2.10, an authentication bypass vulnerability in FUXA allows an unauthenticated, remote attacker to gain administrative access via the heartbeat refresh API and execute arbitrary code on the server. This issue has been patched in FUXA version 1.2.10.
Earn your free CTEM certification.
Learn to scope, prioritize, validate and mobilize fixes for CVEs like CVE-2026-28806 with a free CTEM certification.
Beginner / Practitioner / Program Leader
Explore certifications