metacat: Improper Neutralization of Special Elements used in an SQL Command
CVE-2026-48528 is a critical-severity improper neutralization of special elements used in an SQL command vulnerability in metacat from NCEAS, with a CVSS 3.1 base score of 9.8 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. Affected metacat versions: >= 2.0.0, < 3.4.1. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.47% chance of exploitation within 30 days, which is low compared with other CVEs.
Critical severity: a successful attack would have severe impact.
What to do
- Check which version of metacat you run against the affected versions below, and install the vendor's latest release.
- 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
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
- HighData or code can be modified at will.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H. Scored by CNA (github.com).
Official description
Metacat is data repository software that helps researchers preserve, share, and discover data. Metacat versions 2.0.0 through 3.4.0 contain an unauthenticated SQL injection vulnerability in the `/cn/v1/object` and `/cn/v2/object` REST API endpoints due to unsanitized user input that can be passed through to the backend SQL database. The `nodeId` parameter can be modified to inject SQL commands, and the results are returned in error messages. Metacat appends the user-supplied data into the sql query without sanitization or parameterization. This allows extraction of arbitrary data from the underlying PostgresQL database, fully exposing protected information to the attacker. This is accomplished by leveraging the error reporting mechanisms in Metacat, where SQL error responses are mirrored back to the caller in the XML error message returned by Metacat. One approach, for example, is to use the PostgreSQL `CAST` function to generate an error with the results of an arbitrary subquery, which is then injected into the XML error message returned by Metacat. Attackers do not need to be authenticated to execute the attack. In addition, arbitrary SQL statements that insert, update, and delete data in the Metacat database can be executed, resulting in full compromise of all data in the database. Full proof of concept attacks have been developed and verified for these vulnerabilities. The impact of this vulnerability is critical for Metacat deployments in the DataONE network where information from the database can be exfiltrated, added, changed, or deleted. This includes management information about the data catalog, access log information about who accessed data, identifying information about individuals including their ORCID identifier and client IP address, access control information about who should be able to access and modify data, and other critical internals of the data system. This sql injection vulnerability was remediated fully in Metacat version 3.4.1. If upgrading to Metacat 3.4.1 isn't immediately possible, most deployments can mitigate the issue by disabling the `/cn` REST endpoints in the webapp deployment. This API is not needed or used by member repositories in the DataONE network, as it is only used by the DataONE Coordinating Node deployments. Consequently, this API can be disabled without reduction of functionality for most deployments. To disable the vulnerable endpoints, simply remove the servlet and servlet-mapping for the `/cn` endpoints in the servlet engine associated with the two servlets, `edu.ucsb.nceas.metacat.restservice.v1.CNRestServlet` and `edu.ucsb.nceas.metacat.restservice.v2.CNRestServlet`. For example, in Tomcat, remove the relevant `servlet-mapping` elements from the application web.xml file in Metacat.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Improper Neutralization of Special Elements used in an SQL Command
The product constructs all or part of an SQL command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended SQL command when it is sent to a downstream component. Without sufficient removal or quoting of SQL syntax in user-controllable inputs, the generated SQL query can cause those inputs to be interpreted as SQL instead of ordinary user data.
How developers prevent this class of flaw
- 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 persistence layers such as Hibernate or Enterprise Java Beans, which can provide significant protection against SQL injection if used properly.
- For any security checks that are performed on the client side, ensure that these checks are duplicated on the server side, in order to avoid CWE-602. Attackers can bypass the client-side checks by modifying values after the checks have been performed, or by changing the client to remove the client-side checks entirely. Then, these modified values would be submitted to the server.
- When the set of acceptable objects, such as filenames or URLs, is limited or known, create a mapping from a set of fixed input values (such as numeric IDs) to the actual filenames or URLs, and reject all other inputs.
More Improper Neutralization of Special Elements used in an SQL Command vulnerabilities (CWE-89)
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: yes, technical impact: total).
- Record last changed materially (score, affected products, status or references).
References
Other vulnerabilities in metacat
- 9.3 Critical severity
- 9.8 Critical severity
Recent Improper Neutralization of Special Elements used in an SQL Command vulnerabilities
- 8.6 High severity
- 9.2 Critical severity
- 8.6 High severity
- 10.0 Critical severity
- 8.6 High severity
- 9.8 Critical severity
Spotted an error? Tell us.