CVE-2026-55998
Cluster Existence Oracle via Unauthenticated Import Endpoint
Description
The endpoint /v3/import/{token}_{clusterId}.yaml retrieves the cluster object before validating the token. When a valid cluster ID references a cluster that has private registry secrets configured, a nil pointer dereference in pkg/systemtemplate/private_registry.go causes the request to return HTTP 502 Bad Gateway. For cluster IDs that do not exist, the endpoint returns HTTP 200. This observable difference in response codes constitutes a reliable enumeration oracle.
INFO
Published Date :
Aug. 5, 2026, 8:16 a.m.
Last Modified :
Aug. 5, 2026, 8:16 a.m.
Remotely Exploit :
Yes !
Source :
[email protected]
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | MEDIUM | 404e59f5-483d-4b8a-8e7a-e67604dd8afb | ||||
| CVSS 3.1 | MEDIUM | [email protected] | ||||
| CVSS 3.1 | MEDIUM | MITRE-CVE |
Solution
- Validate token before retrieving cluster object.
- Handle missing or invalid cluster IDs consistently.
- Fix nil pointer dereference in private registry logic.
- Ensure consistent error responses for all cases.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-55998.
| URL | Resource |
|---|---|
| https://bugzilla.suse.com/show_bug.cgi?id=CVE-2026-55998 | |
| https://github.com/rancher/rancher/security/advisories/GHSA-23h9-rr79-r3gh |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-55998 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-55998
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-55998 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-55998 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
New CVE Received by [email protected]
Aug. 05, 2026
Action Type Old Value New Value Added Affected [{'vendor': 'SUSE', 'product': 'Rancher', 'versions': [{'status': 'affected', 'version': '2.14.0', 'lessThan': '2.14.4', 'versionType': 'semver'}, {'status': 'affected', 'version': '2.13.0', 'lessThan': '2.13.8', 'versionType': 'semver'}, {'status': 'affected', 'version': '2.12.0', 'lessThan': '2.12.12', 'versionType': 'semver'}, {'status': 'affected', 'version': '2.11.0', 'lessThan': '2.11.16', 'versionType': 'semver'}], 'packageName': 'Rancher', 'defaultStatus': 'unaffected'}] Added Description The endpoint /v3/import/{token}_{clusterId}.yaml retrieves the cluster object before validating the token. When a valid cluster ID references a cluster that has private registry secrets configured, a nil pointer dereference in pkg/systemtemplate/private_registry.go causes the request to return HTTP 502 Bad Gateway. For cluster IDs that do not exist, the endpoint returns HTTP 200. This observable difference in response codes constitutes a reliable enumeration oracle. Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N Added CWE CWE-204 Added Reference https://bugzilla.suse.com/show_bug.cgi?id=CVE-2026-55998 Added Reference https://github.com/rancher/rancher/security/advisories/GHSA-23h9-rr79-r3gh