MongoDB has disclosed a high‑severity vulnerability, tracked as CVE‑2025‑14847, that could allow unauthenticated remote code execution (RCE). The flaw stems from the Zlib compression handler and can be exploited with low complexity, posing a serious risk to data confidentiality and overall system integrity. Read the Cybersecurity Threat Advisory now for remediation steps to protect your environment.
What is the threat?
The vulnerability arises from improper handling of mismatched length fields in Zlib‑compressed protocol messages. By sending a specially crafted message, an attacker can cause the MongoDB server to leak uninitialized heap memory. This memory exposure can then be used to gain arbitrary code execution and full server compromise.
The issue affects a wide range of MongoDB versions across both current and legacy branches. Fixed versions include:
- 8.2.3 (8.2.0–8.2.2 are vulnerable)
- 8.0.17 (8.0.0–8.0.16 are vulnerable)
- 7.0.28 (7.0.0–7.0.26 are vulnerable)
- 6.0.27 (6.0.0–6.0.26 are vulnerable)
- 5.0.32 (5.0.0–5.0.31 are vulnerable)
- 4.4.30 (4.4.0–4.4.29 are vulnerable)
Older branches (4.2, 4.0, 3.6) also remain vulnerable but may no longer receive mainstream security patches, making immediate migration mandatory.
Why is it noteworthy?
The flaw can be exploited simply by reaching the database’s TCP port (default 27017). No credentials or user interaction are required, making the vulnerability ideal for automated scanning and widespread exploitation. Attacks may go unnoticed because they do not necessarily produce service failures or clear log entries. Exposed memory may reveal sensitive information—including internal structures or code execution primitives—that attackers can use to escalate into full compromise.
What is the exposure or risk?
A successful exploit may expose PII, database content, or sensitive memory data such as session tokens or hashed passwords. If attackers extend the memory leak into RCE, they can gain persistent control of the underlying system, deploy ransomware, exfiltrate data, or pivot deeper into the environment.
What are the recommendations?
Barracuda recommends the following actions to secure your systems against this vulnerability:
- Upgrade all MongoDB instances to the latest fixed releases.
- If upgrading is temporarily infeasible, disable zlib compression by adjusting the server startup parameters (networkMessageCompressors / net.compression.compressors) to exclude zlib.
- Restrict access to MongoDB ports from untrusted networks via firewall rules or ACLs.
References
For more in-depth information about the recommendations, please visit the following links:
- https://www.bleepingcomputer.com/news/security/mongodb-warns-admins-to-patch-severe-rce-flaw-immediately/
- https://orca.security/resources/blog/cve-2025-14847-mongodb-heap-memory-leak/
If you have any questions about this Cybersecurity Threat Advisory, don’t hesitate to get in touch with Barracuda Managed XDR’s Security Operations Center.
This post originally appeared on Smarter MSP.