CVE-2021-31920 : What You Need to Know

A vulnerability has been identified in Istio versions before 1.8.6 and 1.9.5 that allows an attacker to potentially bypass Istio's authorization policy. This occurs when an HTTP request path contains multiple slashes or escaped slash characters.

Understanding CVE-2021-31920

This CVE highlights a security flaw in Istio versions prior to 1.8.6 and 1.9.5 that could be exploited by an attacker to circumvent authorization policies.

What is CVE-2021-31920?

The vulnerability in CVE-2021-31920 allows malicious actors to bypass Istio authorization policies by manipulating the HTTP request path with specific characters.

The Impact of CVE-2021-31920

The exploit in CVE-2021-31920 could lead to unauthorized access within affected Istio versions, potentially compromising the security of the system.

Technical Details of CVE-2021-31920

This section delves into the technical specifics of CVE-2021-31920, shedding light on the nature of the vulnerability.

Vulnerability Description

Istio versions before 1.8.6 and 1.9.5 are susceptible to a remote exploit where specially crafted HTTP request paths can bypass authorization policies.

Affected Systems and Versions

The impacted systems include Istio instances running versions prior to 1.8.6 and 1.9.5, exposing them to the risk of unauthorized access.

Exploitation Mechanism

By inserting multiple slashes or escaped characters into the HTTP request path, threat actors can potentially evade Istio's authorization controls.

Mitigation and Prevention

In this section, actionable steps to address and mitigate the risks associated with CVE-2021-31920 are outlined.

Immediate Steps to Take

Istio users are advised to update their installations to versions 1.8.6 or 1.9.5 to patch the vulnerability and prevent unauthorized access.

Long-Term Security Practices

Maintaining regular updates and security best practices can strengthen the overall defense posture against similar exploits in the future.

Patching and Updates

Regularly applying patches and monitoring security advisories can help in staying ahead of emerging threats and safeguarding Istio environments.