nerves_hub_web: Authorization Bypass Through User-Controlled Key
CVE-2026-120730 is a high-severity authorization bypass through user-controlled key vulnerability in nerves_hub_web from Nerves-hub, with a CVSS 4.0 base score of 8.6 out of 10. It can be exploited remotely over the network by an attacker with a low-privileged account, without any action from a user. The record lists versions 2.5.3, c367d7d17d07f843e78a70d15904665616dde964 as the first without the flaw, so updating nerves_hub_web to one of those releases or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.36% chance of exploitation within 30 days, which is low compared with other CVEs.
High severity with no evidence of exploitation so far.
What to do
- Update nerves_hub_web to 2.5.3 or c367d7d17d07f843e78a70d15904665616dde964, whichever matches your release line, or a later version.
- Read the advisory on github.com for workarounds and exact fixed builds.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Nerves-hub | nerves_hub_web | 1.0.0 up to, but not including, 2.5.3; f58d58233dbd355c58d3a140107ece18e8863f14 up to, but not including, c367d7d17d07f843e78a70d15904665616dde964 | 2.5.3, c367d7d17d07f843e78a70d15904665616dde964 |
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- NetworkCan be exploited remotely over a network, including the internet.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Attack requirements
- NoneThe attack does not depend on a particular deployment or configuration.
- Privileges required
- LowA basic user account is enough.
- User interaction
- NoneNo action by a victim is required.
- Confidentiality (vulnerable system)
- HighSerious loss of confidentiality on the vulnerable system.
- Integrity (vulnerable system)
- HighSerious loss of integrity on the vulnerable system.
- Availability (vulnerable system)
- NoneNo loss of availability on the vulnerable system.
- Confidentiality (other systems)
- NoneNo loss of confidentiality on systems beyond the vulnerable one.
- Integrity (other systems)
- NoneNo loss of integrity on systems beyond the vulnerable one.
- Availability (other systems)
- NoneNo loss of availability on systems beyond the vulnerable one.
Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/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. Scored by CNA.
Official description
Improperly Controlled Modification of Dynamically-Determined Object Attributes vulnerability in the device API, device forms, signing key and product forms and JITP settings in nerves-hub nerves_hub_web allows an authenticated user who manages devices in any organization to write into other organizations via submitted org_id, product_id and deployment_id fields. The device API create and update actions and the dashboard device forms pass the request parameters to NervesHub.Devices.Device.changeset/2, which casts the organization, product, deployment group and update state as given. The signing key and product forms merge the session's organization into the submitted parameters so that a submitted org_id wins, and the JITP changeset accepts any product_id. Each request requires the manage role only in the user's own organization, and any account can create one. A device placed on another organization's deployment group, or moved into its product, is sent that organization's firmware with a download URL. The user cannot change or control devices that already belong to the other organization, and cannot upload firmware to it. This issue affects nerves_hub: from 1.0.0 before 2.5.3.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Authorization Bypass Through User-Controlled Key
The system's authorization functionality does not prevent one user from gaining access to another user's data or record by modifying the key value identifying the data.
How developers prevent this class of flaw
- For each and every data access, ensure that the user has sufficient privilege to access the record that is being requested.
- Make sure that the key that is used in the lookup of a specific user's record is not controllable externally by the user or that any tampering can be detected.
- Use encryption in order to make it more difficult to guess other legitimate values of the key or associate a digital signature with the key so that the server can verify that there has been no tampering.
More Authorization Bypass Through User-Controlled Key vulnerabilities (CWE-639)
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: poc, automatable: no, technical impact: total).
- Record last changed materially (score, affected products, status or references).
References
Patches and release notes
Other vulnerabilities in nerves_hub_web
- 7.4 High severity
- 7.1 High severity
- 9.4 Critical severity
- 8.8 High severity
- 9.8 Critical severity
Recent Authorization Bypass Through User-Controlled Key vulnerabilities
- 7.5 High severity
- 7.1 High severity
- 7.1 High severity
- 8.1 High severity
- 9.9 Critical severity
- 7.1 High severity
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