CVE-2020-8559

Description

A flaw was found in the Kubernetes API server, where it allows an attacker to escalate their privileges from a compromised node. This flaw allows an attacker who can intercept requests on a compromised node, to redirect those requests, along with their credentials, to perform actions on other endpoints that trust those credentials (including other clusters), allowing for escalation of privileges. The highest threat from this vulnerability is to confidentiality, integrity, and system availability.

Statement

Kubernetes is embedded in the version of heketi shipped with Red Hat Gluster Storage 3. However, it does not use Kubernetes API server part and only uses client side bits. Hence, this flaw does not affect heketi.

Mitigation

No mitigation is known.

Common Vulnerability Scoring System (CVSS) Score Details

Info alert:Important note

CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).

CVSS v3 Score Breakdown

Red HatNVDcve.org
Base Score6.46.8N/A
Attack VectorNetworkNetworkN/A
Attack ComplexityHighLowN/A
Privileges RequiredHighHighN/A
User InteractionRequiredRequiredN/A
ScopeUnchangedUnchangedN/A
ConfidentialityHighHighN/A
Integrity ImpactHighHighN/A
Availability ImpactHighHighN/A

Vector

Red Hat: CVSS:3.1/AV:N/AC:H/PR:H/UI:R/S:U/C:H/I:H/A:H

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

Understanding the Weakness (CWE)

Access Control

Technical Impact: Bypass Protection Mechanism; Gain Privileges or Assume Identity

The user may be redirected to an untrusted page that contains malware which may then compromise the user's system. In some cases, an open redirect can also enable the immediate download of a file without the user's permission, because the redirection to an external site may lead to endpoints on those sites that automatically trigger a download action ("drive-by download" [REF-1478]). This will expose the user to extensive risk. The user's interaction with the web server may also be compromised if the malware conducts keylogging or other attacks that steal credentials, personally identifiable information (PII), or other important data.

Access Control,Confidentiality,Other

Technical Impact: Bypass Protection Mechanism; Gain Privileges or Assume Identity; Other

By modifying the URL value to a malicious site, an attacker may successfully launch a phishing scam. The user may be subjected to phishing attacks by being redirected to an untrusted page. The phishing attack may point to an attacker controlled web page that appears to be a trusted web site. The phishers may then steal the user's credentials and then use these credentials to access the legitimate web site. Because the server name in the modified link is identical to the original site, phishing attempts have a more trustworthy appearance.

Acknowledgements

Red Hat would like to thank the Kubernetes Product Security Committee for reporting this issue. Upstream acknowledges Wouter ter Maat (Offensi) as the original reporter.

Frequently Asked Questions

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