Apache Solr: Improper Authorization
CVE-2026-22022 is a high-severity improper authorization vulnerability in Apache Solr from Apache, with a CVSS 3.1 base score of 8.2 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. Affected Apache Solr versions: 5.3 through 9.10.0. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.57% 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 Solr to 9.10.1 or a later version.
- Read the advisory on lists.apache.org 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 |
|---|---|---|---|
| Apache | Apache Solr | 5.3 through 9.10.0 | Not stated |
| Apache | Solr | 5.3.0 up to, but not including, 9.10.1 | 9.10.1 |
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
- LowLimited modification of data is possible.
- Availability
- NoneAvailability is not affected.
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:N. Scored by CISA (ADP).
Official description
Deployments of Apache Solr 5.3.0 through 9.10.0 that rely on Solr's "Rule Based Authorization Plugin" are vulnerable to allowing unauthorized access to certain Solr APIs, due to insufficiently strict input validation in those components. Only deployments that meet all of the following criteria are impacted by this vulnerability: * Use of Solr's "RuleBasedAuthorizationPlugin" * A RuleBasedAuthorizationPlugin config (see security.json) that specifies multiple "roles" * A RuleBasedAuthorizationPlugin permission list (see security.json) that uses one or more of the following pre-defined permission rules: "config-read", "config-edit", "schema-read", "metrics-read", or "security-read". * A RuleBasedAuthorizationPlugin permission list that doesn't define the "all" pre-defined permission * A networking setup that allows clients to make unfiltered network requests to Solr. (i.e. user-submitted HTTP/HTTPS requests reach Solr as-is, unmodified or restricted by any intervening proxy or gateway) Users can mitigate this vulnerability by ensuring that their RuleBasedAuthorizationPlugin configuration specifies the "all" pre-defined permission and associates the permission with an "admin" or other privileged role. Users can also upgrade to a Solr version outside of the impacted range, such as the recently released Solr 9.10.1.
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: none, automatable: yes, technical impact: partial).
- Record last changed materially (score, affected products, status or references).
References
Advisories
Third-party and government advisories
- openwall.com/lists/oss-security/2026/01/20/4Mailing List, Third Party Advisory
Other vulnerabilities in Apache Solr
- 9.8 Critical severity
- 7.1 High severity
- 8.1 High severity
- 9.8 Critical severity
- 8.8 High severity
- 7.5 High severity
Recent Improper Authorization vulnerabilities
- 9.9 Critical severity
- 8.8 High severity
- 9.8 Critical severity
- 9.8 Critical severity
- 9.6 Critical severity
- 8.1 High severity
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