CVE-2020-1741

Description

A flaw was found in openshift-ansible. OpenShift Container Platform (OCP) 3.11 is too permissive in the way it specified CORS allowed origins during installation. An attacker, able to man-in-the-middle the connection between the user's browser and the openshift console, could use this flaw to perform a phishing attack. The main threat from this vulnerability is data confidentiality.

Mitigation

Ensure that the corsAllowedOrigin definition within master-config.yaml contains elements in the form

corsAllowedOrigins:
- ^(?i)https://my\.subdomain\.domain\.com(:|\z)

and not the form

corsAllowedOrigins:
- (?i)//my\.subdomain\.domain\.com(:|\z)

as the first will permit cross origin requests only if the host and protocol matches, whereas the second will permit a downgrade to http protocol for example.

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 Score5.95.9N/A
Attack VectorNetworkNetworkN/A
Attack ComplexityHighHighN/A
Privileges RequiredNoneNoneN/A
User InteractionRequiredRequiredN/A
ScopeUnchangedUnchangedN/A
ConfidentialityHighHighN/A
Integrity ImpactLowLowN/A
Availability ImpactNoneNoneN/A

Vector

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

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

Understanding the Weakness (CWE)

Other

Technical Impact: Unexpected State; Varies by Context

When the regular expression is not correctly specified, data might have a different format or type than the rest of the program expects, producing resultant weaknesses or errors.

Access Control

Technical Impact: Bypass Protection Mechanism

In PHP, regular expression checks can sometimes be bypassed with a null byte, leading to any number of weaknesses.

Frequently Asked Questions

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