Capgo: Improper Authorization
CVE-2026-56231 is a high-severity improper authorization vulnerability in Capgo, with a CVSS 3.1 base score of 7.6 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 version 12.128.2 as the first without the flaw, so updating Capgo to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.31% 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 Capgo to 12.128.2 or a later version.
- Read the advisory on github.com for workarounds and exact fixed builds.
Affected products and versions
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.
- Privileges required
- LowA basic user account is enough.
- User interaction
- NoneNo action by a victim is required.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- LowSome restricted data can be read.
- Integrity
- LowLimited modification of data is possible.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:H. Scored by CNA (vulncheck.com).
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 4.0 | 7.2 | High | CNA (vulncheck.com) |
| CVSS 3.1 | 7.6 | High | CNA (vulncheck.com) |
Official description
Capgo before 12.128.2 contains a broken object level authorization (BOLA) vulnerability in the POST /build/start/:jobId and POST /build/cancel/:jobId endpoints. The handlers authorize the request based only on the attacker-controlled app_id supplied in the request body and never verify that the jobId in the URL belongs to that app_id (or the same tenant/org) before issuing privileged builder commands with the server-held builder API key. An authenticated user with the app.build_native permission for any app they control can start or cancel arbitrary builder jobs belonging to other tenants by supplying a victim jobId, resulting in cross-tenant build sabotage (denial of service), unauthorized compute actions, and potential billing impact.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Improper Authorization
The product does not perform or incorrectly performs an authorization check when an actor attempts to access a resource or perform an action.
How developers prevent this class of flaw
- Divide the product into anonymous, normal, privileged, and administrative areas. Reduce the attack surface by carefully mapping roles with data and functionality. Use role-based access control (RBAC) to enforce the roles at the appropriate boundaries. Note that this approach may not protect against horizontal authorization, i.e., it will not protect a user from attacking others with the same role.
- Ensure that you perform access control checks related to your business logic. These checks may be different than the access control checks that you apply to more generic resources such as files, connections, processes, memory, and database records. For example, a database may restrict access for medical records to a specific database user, but each record might only be intended to be accessible to the patient and the patient's doctor.
- Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid. For example, consider using authorization frameworks such as the JAAS Authorization Framework and the OWASP ESAPI Access Control feature.
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: poc, automatable: no, technical impact: partial).
- Record last changed materially (score, affected products, status or references).
References
Other references
Other vulnerabilities in Capgo
- 8.1 High severity
- 7.3 High severity
- 8.3 High severity
- 7.5 High severity
- 7.5 High severity
- 8.3 High severity
Recent Improper Authorization vulnerabilities
- 7.1 High severity
- 7.1 High severity
- 7.8 High severity
- 7.5 High severity
- 7.3 High severity
- 8.8 High severity
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