CoreOS Tectonic up to 1.7.9/1.8.4 /api/kubernetes/ information disclosure

Summaryinfo

A vulnerability classified as problematic has been found in CoreOS Tectonic up to 1.7.9/1.8.4. This affects an unknown part of the file /api/kubernetes/. The manipulation leads to information disclosure. This vulnerability is uniquely identified as CVE-2018-5256. The attack is possible to be carried out remotely. No exploit exists.

Detailsinfo

A vulnerability was found in CoreOS Tectonic up to 1.7.9/1.8.4 and classified as problematic. This issue affects some unknown processing of the file /api/kubernetes/. The manipulation with an unknown input leads to a information disclosure vulnerability. Using CWE to declare the problem leads to CWE-200. The product exposes sensitive information to an actor that is not explicitly authorized to have access to that information. Impacted is confidentiality. The summary by CVE is:

CoreOS Tectonic 1.7.x before 1.7.9-tectonic.4 and 1.8.x before 1.8.4-tectonic.3 mounts a direct proxy to the kubernetes cluster at /api/kubernetes/ which is accessible without authentication to Tectonic and allows an attacker to directly connect to the kubernetes API server. Unauthenticated users are able to list all Namespaces through the Console, resulting in an information disclosure. Tectonic's exposure of an unauthenticated API endpoint containing information regarding the internal state of the cluster can provide an attacker with information that may assist in other attacks against the cluster. For example, an attacker may not have the permissions required to list all namespaces in the cluster but can instead leverage this vulnerability to enumerate the namespaces and then begin to check each namespace for weak authorization policies that may allow further escalation of privileges.

The bug was discovered 01/05/2018. The weakness was disclosed 05/18/2018 (Website). The advisory is shared at coreos.com. The identification of this vulnerability is CVE-2018-5256 since 01/07/2018. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. Technical details are known, but no exploit is available. MITRE ATT&CK project uses the attack technique T1592 for this issue.

The vulnerability was handled as a non-public zero-day exploit for at least 133 days. During that time the estimated underground price was around $0-$5k.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Name

• CoreOS Tectonic

Version

• 1.7.0
• 1.7.1
• 1.7.2
• 1.7.3
• 1.7.4
• 1.7.5
• 1.7.6
• 1.7.7
• 1.7.8
• 1.7.9
• 1.8.0
• 1.8.1
• 1.8.2
• 1.8.3
• 1.8.4

CPE 2.3info

• 🔍
• 🔍
• 🔍

CPE 2.2info

• 🔍
• 🔍
• 🔍

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Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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