External risk intelligence

Apache Shiro Remote Code Execution Vulnerability.

CVE advisoryKnown Exploit

CVE-2016-4437

A vulnerability in Apache Shiro's "remember me" feature can allow remote attackers to execute code or bypass access restrictions if a cipher key is not configured. This impacts organizations by enabling unauthorized system access and potential data compromise. The business risk includes exposure of sensitive informatio

4Halo Surface Signal

Apache Aurora

0.10.0 to before 0.18.1before 1.2.51.0

External exposure likelihood

Halo Surface Signal score for CVE-2016-4437

Apache Shiro is a widely used security framework integrated into numerous web applications and enterprise services to handle authentication and session management. As a core component of web-facing applications, this vulnerability in the 'remember me' feature is commonly exposed to the public internet through standard web traffic.

Horizon Alert

Summary of the vulnerability and why it matters

Apache Shiro, a framework used for authentication and session management, contains a vulnerability that could permit unauthorized code execution or access bypass. The flaw resides within the "remember me" functionality when a specific security key is not configured. This could allow attackers to compromise systems and access sensitive information.

Vulnerable component: Apache Shiro "remember me" feature
Core weakness: Unconfigured cipher key
Main business impact: Code execution or access bypass

Attack Path

How an attacker could exploit the issue

Attackers can exploit a misconfiguration in the Apache Shiro framework to gain unauthorized access. If the cipher key for the "remember me" functionality is not set, remote attackers can send a crafted request to bypass security controls. This allows for the execution of arbitrary code, potentially leading to a complete compromise of the affected system. The impact on organizations includes unauthorized data access, system manipulation, and potential disruption of business operations.

Unconfigured cipher key exposure
Attacker sends crafted request
Arbitrary code execution and access bypass

Live Threat

Current exploitation, exposure, and threat context

This vulnerability poses a significant risk to organizations utilizing the affected Apache Shiro software. Remote attackers with no special privileges can potentially execute arbitrary code or bypass access controls. This could lead to unauthorized access, data compromise, and disruption of services, indicating a high level of business risk.

Low attacker skill level required.
No authentication or special conditions needed.
High business risk; treat as urgent.

Priority actions

Operational Fix

Recommended remediation, mitigation, and detection steps

This vulnerability in Apache Shiro can allow remote attackers to execute arbitrary code or bypass access controls. The risk is heightened when a cipher key is not configured for the \"remember me\" feature. Organizations should prioritize identifying all instances of affected software within their environment to understand the potential impact.

Find assets using Apache Shiro.
Reduce exposure or isolate affected systems.
Apply vendor fixes and verify implementation.
Monitor for related security events.

Frequently asked questions

What is the Apache Shiro "remember me" feature vulnerability, and what kind of weakness does it involve?

Apache Shiro versions prior to 1.2.5 have a vulnerability in the "remember me" feature. This weakness, classified as CWE-284 (Improper Access Control), allows remote attackers to execute arbitrary code or bypass intended access restrictions if a cipher key has not been configured.

How can attackers exploit the Apache Shiro vulnerability, and what is the scope of the bypass?

Attackers can exploit this vulnerability by sending a specially crafted, unspecified request parameter when the cipher key for the "remember me" feature is not configured. This allows them to bypass intended access restrictions and potentially execute arbitrary code on the affected system, impacting all users and processes on that system.

What is the relevance of CVE-2016-4437, especially considering its listing on the CISA Known Exploited Vulnerabilities Catalog?

CVE-2016-4437 is highly relevant due to its presence on the CISA Known Exploited Vulnerabilities Catalog, indicating active exploitation. This means adversaries are actively using this vulnerability, posing a significant and immediate threat to organizations.

How does Halo's threat intelligence classify the exposure risk of Apache Shiro's "remember me" vulnerability?

Halo classifies this CVE as having a 'Likely' exposure risk. This is because Apache Shiro is a widely used security framework in web applications, and this vulnerability within the "remember me" feature is often exposed to the public internet.

What are the immediate steps an organization should take to address the Apache Shiro "remember me" vulnerability?

Organizations should urgently identify all instances of affected Apache Shiro software. It is critical to reduce exposure by isolating affected systems if possible, and then apply vendor-provided fixes and verify their successful implementation. Continuous monitoring for related security events is also recommended.

References

Written by Nicholas Merritt

External-surface CVE analysis and Halo Surface Signal prioritization for Halo Threat Intelligence.