CVE-2021-32687 : Vulnerability Insights and Analysis

This article provides detailed information about CVE-2021-32687, an integer overflow vulnerability affecting Redis.

Understanding CVE-2021-32687

CVE-2021-32687 is an integer overflow bug in Redis that impacts all versions, allowing malicious actors to corrupt the heap and potentially execute remote code.

What is CVE-2021-32687?

Redis, an open-source in-memory database, is vulnerable to an integer overflow issue that can be exploited to trigger remote code execution. The vulnerability arises from manipulation of the set-max-intset-entries configuration parameter.

The Impact of CVE-2021-32687

The vulnerability has a high severity rating with an overall CVSS base score of 7.5. It poses a high risk to system confidentiality, integrity, and availability. Attackers can abuse this flaw to leak sensitive information or execute arbitrary code remotely.

Technical Details of CVE-2021-32687

This section covers the specific technical aspects of the CVE.

Vulnerability Description

The vulnerability stems from an integer overflow issue in the intsets of Redis. By setting the

set-max-intset-entries

configuration parameter to a large value, attackers can manipulate sets and compromise the database.

Affected Systems and Versions

Redis versions < 5.0.14, >= 6.0.0, < 6.0.16, and >= 6.2.0, < 6.2.6 are affected by this vulnerability.

Exploitation Mechanism

The vulnerability can be exploited through crafted commands that manipulate sets, leading to potential heap corruption and remote code execution.

Mitigation and Prevention

To secure systems against CVE-2021-32687, implement the following strategies.

Immediate Steps to Take

Update Redis to version 6.2.6, 6.0.16, or 5.0.14 to fix the issue. Additionally, restrict user access to the

CONFIG SET

command to prevent the manipulation of critical parameters.

Long-Term Security Practices

Regularly monitor Redis security advisories and apply patches promptly to mitigate emerging threats.

Patching and Updates

Stay informed about security updates from Redis to protect against known vulnerabilities.