Strix
26.1K

CVE-2018-5256

HIGHCVSS 7.5/10EPSS 1.67%

Last modified

CVE-2018-5256 is a high-severity vulnerability rated 7.5/10 on the CVSS scale. 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. EPSS estimates a 1.67% chance of exploitation in the next 30 days.

Description

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.

Metrics

CVSS 3.1
7.5/10

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

EPSS Probability
1.67%

73.8th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

VendorProductVersions
RedhatTectonic>= 1.7.1-tectonic.1, < 1.7.9-tectonic.4
RedhatTectonic>= 1.8.4-tectonic.1, < 1.8.4-tectonic.3

References

Timeline

Published
Last Modified
Status
Modified

Frequently Asked Questions

What is CVE-2018-5256?
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.
How severe is CVE-2018-5256?
CVE-2018-5256 has a CVSS score of 7.5/10 (HIGH severity). The EPSS model estimates a 1.67% probability of exploitation in the next 30 days.
How do I fix CVE-2018-5256?
Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2018-5256?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST