security-advisories: Incorrect Authorization
CVE-2022-36074 is a high-severity incorrect authorization vulnerability in security-advisories from Nextcloud, with a CVSS 3.1 base score of 7.5 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. Affected security-advisories versions: < 23.0.7; >= 24.0.0, < 24.0.3. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.77% chance of exploitation within 30 days, higher than 56% of scored CVEs.
High severity with no evidence of exploitation so far.
What to do
- Update Nextcloud Enterprise Server to 22.2.11 or 23.0.7 or 24.0.3, whichever matches your release line, or a later version.
- Update Nextcloud Server to 23.0.7 or 24.0.3, whichever matches your release line, or a later version.
- Read the advisory on github.com for workarounds and exact fixed builds.
- Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Nextcloud | security-advisories | < 23.0.7; >= 24.0.0, < 24.0.3 | Not stated |
| Nextcloud | Nextcloud Enterprise Server | before 22.2.11; 23.0.0 up to, but not including, 23.0.7; 24.0.0 up to, but not including, 24.0.3 | 22.2.11, 23.0.7, 24.0.3 |
| Nextcloud | Nextcloud Server | before 23.0.7; 24.0.0 up to, but not including, 24.0.3 | 23.0.7, 24.0.3 |
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
- NoneNo account or login is needed.
- User interaction
- NoneNo action by a victim is required.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- HighAll data handled by the component can be read.
- Integrity
- NoneNothing can be modified.
- Availability
- NoneAvailability is not affected.
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N. Scored by NVD.
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 3.1 | 6.4 | Medium | CNA (github.com) |
| CVSS 3.1 | 7.5 | High | NVD |
Official description
Nextcloud server is an open source personal cloud product. Affected versions of this package are vulnerable to Information Exposure which fails to strip the Authorization header on HTTP downgrade. This can lead to account access exposure and compromise. It is recommended that the Nextcloud Server is upgraded to 23.0.7 or 24.0.3. It is recommended that the Nextcloud Enterprise Server is upgraded to 22.2.11, 23.0.7 or 24.0.3. There are no known workarounds for this issue.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Incorrect Authorization
The product performs an authorization check when an actor attempts to access a resource or perform an action, but it does not correctly perform the check.
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 access control checks are performed related to the business logic. These checks may be different than the access control checks that are applied 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: none, automatable: no, technical impact: total).
- Record last changed materially (score, affected products, status or references).
References
Advisories
- github.com/nextcloud/security-advisories/security/advisories/GHSA-vqgm-f748-g76vThird Party Advisory
Patches and release notes
- github.com/nextcloud/server/pull/32941Third Party Advisory
Other vulnerabilities in security-advisories
- 7.1 High severity
- 8.2 High severity
- 8.8 High severity
- 8.1 High severity
- 8.1 High severity
Recent Incorrect Authorization vulnerabilities
- 8.8 High severity
- 7.1 High severity
- 7.1 High severity
- 9.8 Critical severity
- 8.1 High severity
- 8.8 High severity
Spotted an error? Tell us.