Critical Flaw CVE-2025-49844 (CVSS 10.0) Allows Remote Code Execution in Redis

Estimated reading time: 8 minutes

Key Takeaways:

  • A critical RCE vulnerability (CVE-2025-49844) affects Redis versions with Lua scripting support.
  • Exploitation could lead to complete system compromise and data breaches.
  • Immediate patching and mitigation strategies are crucial to reduce risk.
  • PurpleOps offers services to help organizations protect against these threats.

Table of Contents:

A critical remote code execution (RCE) vulnerability, identified as CVE-2025-49844 (CVSS 10.0), has been discovered in Redis. This flaw impacts all Redis versions that include Lua scripting support, posing a significant risk to systems using the popular in-memory data store. The vulnerability allows an authenticated attacker to execute arbitrary code on the Redis server by exploiting a Use-After-Free bug within the Lua scripting engine.

Redis, known for its speed and versatility in applications such as real-time analytics, caching, and message brokering, has released patches to address this and other related vulnerabilities. Understanding the nature of CVE-2025-49844 and its potential impact is crucial for maintaining the security of systems relying on Redis.

Understanding CVE-2025-49844: A Deep Dive

The vulnerability, CVE-2025-49844, stems from improper memory management within Redis’s embedded Lua interpreter. The core issue is a Use-After-Free bug that can be triggered via a specially crafted Lua script. An authenticated user can manipulate the garbage collection process, exploiting freed memory pointers to execute arbitrary code within the Redis server’s process.

The implications of this flaw are far-reaching. Successful exploitation could lead to the complete compromise of stored data and enable lateral movement to other connected systems. This is because the attacker gains the ability to run code within the context of the Redis server itself.

The Common Vulnerability Scoring System (CVSS) has assigned CVE-2025-49844 a score of 10.0, the highest possible, indicating its critical severity. This score reflects the ease of exploitation and the potential for widespread damage.

Other Redis Vulnerabilities Patched

In addition to CVE-2025-49844, Redis patched three other vulnerabilities related to Lua scripting:

  • CVE-2025-46817 (CVSS 7.0): Integer Overflow in Lua Commands: This vulnerability could lead to remote code execution through a specially crafted Lua script that causes an integer overflow. Improper integer bounds checking within Lua scripts could allow attackers to overwrite memory values, potentially leading to arbitrary instruction execution.
  • CVE-2025-46818 (CVSS 6.0): Running Lua Functions as Another User: This flaw allows privilege escalation between Redis users. By manipulating Lua objects, an authenticated user could run code in the context of another user, potentially accessing or modifying data beyond their permissions. This is particularly concerning in multi-tenant environments.
  • CVE-2025-46819 (CVSS 6.3): Out-of-Bounds Read in Lua Engine: This vulnerability may result in an out-of-bounds read within the Lua engine. An attacker could leak sensitive memory data or crash the Redis server, leading to a denial of service.

Impact on Redis Deployments

These vulnerabilities, particularly CVE-2025-49844, affect a wide range of Redis deployments. All Redis versions that include Lua scripting support are susceptible. This includes both self-hosted and enterprise deployments, making it a universal threat.

The impact on organizations using Redis could be severe. Successful exploitation could lead to:

  • Data breaches: Attackers could gain access to sensitive data stored in Redis.
  • System compromise: Remote code execution allows attackers to take control of the Redis server and potentially other connected systems.
  • Denial of service: The out-of-bounds read vulnerability could crash the Redis server, disrupting services that depend on it.
  • Lateral movement: Attackers could use the compromised Redis server as a springboard to attack other systems within the network.

Mitigation Strategies

Given the severity of these vulnerabilities, immediate action is required to mitigate the risk. Redis has released patched versions to address these flaws.

Recommended steps include:

  1. Upgrade Redis: Upgrade to the latest Redis versions: 6.2.20, 7.2.11, 7.4.6, 8.0.4, or 8.2.2. This is the most effective way to address the vulnerabilities.
  2. Restrict Lua Scripting: Implement access control lists (ACLs) to block the EVAL, EVALSHA, and FUNCTION commands for all non-administrative users. This can prevent attackers from exploiting the Lua scripting vulnerabilities.
  3. Network Segmentation: Isolate Redis servers from external access and limit connections to trusted applications. This can reduce the attack surface and prevent attackers from reaching the Redis server.
  4. Monitor Lua Activity: Implement logging and alerting to monitor for suspicious Lua activity or unusual memory behavior. This can help detect and respond to potential attacks.

By implementing these mitigation strategies, organizations can significantly reduce their risk of exploitation. Regular security audits and penetration testing are also crucial for identifying and addressing potential vulnerabilities. Monitoring your underground forum intelligence and Telegram threat monitoring can also provide early warnings of exploitation attempts.

Practical Takeaways

  • Technical Readers: Apply the patches immediately. If immediate patching is not possible, use ACLs to restrict access to Lua scripting commands. Monitor Redis logs for suspicious activity related to Lua scripting. Incorporate breach detection and supply-chain risk monitoring tools.
  • Non-Technical Readers: Ensure your IT teams are aware of this vulnerability and are taking steps to mitigate the risk. Ask them to confirm that Redis has been patched or that appropriate mitigation measures are in place. Consider investing in cyber threat intelligence platform and real-time ransomware intelligence services to stay ahead of potential threats. Utilize dark web monitoring service to detect potential brand leaks.

How PurpleOps Can Help

PurpleOps provides a range of services that can help organizations protect themselves from vulnerabilities like CVE-2025-49844. Our services include:

  • Cyber Threat Intelligence: We offer cyber threat intelligence services to help organizations stay informed about the latest threats and vulnerabilities, including real-time ransomware intelligence and live ransomware API feeds.
  • Dark Web Monitoring: Our dark web monitoring service can detect mentions of your organization or its data on the dark web, alerting you to potential data breaches or other security incidents.
  • Breach Detection: We provide breach detection services to help organizations identify and respond to security breaches quickly and effectively.
  • Supply Chain Risk Monitoring: Our supply chain information security services can help organizations assess and manage the security risks associated with their supply chain.
  • Red Team Operations: PurpleOps red team operations provide a proactive approach to identifying and exploiting vulnerabilities in your systems, simulating real-world attacks to improve your security posture.
  • Penetration Testing: Our penetration testing services can help you identify vulnerabilities in your systems and applications before attackers do.

By leveraging PurpleOps’ expertise and services, organizations can improve their security posture and protect themselves from the growing number of cyber threats. We can assist with implementing robust security measures, monitoring for suspicious activity, and responding to security incidents effectively.

Explore our platform at https://www.purple-ops.io/platform/ to discover how our cyber threat intelligence, dark web monitoring, and breach detection services can enhance your security posture. Contact us at PurpleOps Solutions for more information and to discuss your specific needs. Protect your organization from evolving cyber threats with PurpleOps.

FAQ

Q: What is CVE-2025-49844?
A: CVE-2025-49844 is a critical remote code execution vulnerability in Redis that allows an attacker to execute arbitrary code on the Redis server.

Q: Which Redis versions are affected?
A: All Redis versions that include Lua scripting support are affected.

Q: What are the mitigation steps?
A: Upgrade to the latest Redis versions, restrict Lua scripting, implement network segmentation, and monitor Lua activity.