{"id":109220,"date":"2026-04-08T14:13:53","date_gmt":"2026-04-08T14:13:53","guid":{"rendered":"https:\/\/www.red-gate.com\/simple-talk\/?p=109220"},"modified":"2026-04-08T15:09:16","modified_gmt":"2026-04-08T15:09:16","slug":"everything-you-need-to-know-about-mongobleed-cve-2025-14847","status":"publish","type":"post","link":"https:\/\/www.red-gate.com\/simple-talk\/cloud\/security-and-compliance\/everything-you-need-to-know-about-mongobleed-cve-2025-14847\/","title":{"rendered":"Everything you need to know about MongoBleed (CVE-2025-14847)"},"content":{"rendered":"\n

MongoBleed (CVE-2025-14847) was defined as \u201cthe vulnerability of the year.\u201d<\/a> In this article, find out what it is, why it’s dangerous, and if (and when) you should care about it. But first, some context.<\/p>\n\n\n\n

Back in April 2014, a vulnerability in the TLS extension ‘Heartbeat’ was discovered by researchers at Google<\/a>. The vulnerability came about because, at the time, OpenSSL<\/a> never properly checked the length of any requested data. Attackers could therefore ‘craft’ requests in such a way that harvested personal data. This vulnerability picked up the quite appropriate moniker ‘Heartbleed’.<\/a><\/p>\n\n\n\n

Heartbleed was dangerous because it focused on leaked memory that could contain highly sensitive information such as private encryption keys<\/a>, usernames, passwords, and more. It had a huge impact – not only because millions of websites and apps used OpenSSL, but it was also hard to detect since the logs associated with it were well hidden.<\/p>\n\n\n\n

So, where does MongoBleed (CVE-2025-14847) come in – and what is it?<\/h2>\n\n\n\n

Servers running MongoDB<\/a> using vulnerable OpenSSL versions can leak memory through the Heartbleed bug. Since MongoDB can use OpenSSL for encrypted (TLS) connections, MongoBleed allows attackers to:<\/p>\n\n\n

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  1. Send a malicious message to keep a TLS session alive (send a TLS \u201eheartbeat\u201c request.)

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  2. Cause the server to return some of its memory – potentially exposing sensitive information stored or processed by MongoDB.<\/li>\n<\/ol>\n<\/div>\n\n\n

    In theory, attackers could access and extract memory data that might contain private keys<\/a>, SQL query<\/a> results stored in memory, or other data. Here\u2018s a full rundown of how MongoBleed compares to Heartbleed:<\/p>\n\n\n\n

    Feature<\/strong><\/td>Heartbleed<\/strong><\/td>MongoBleed<\/strong><\/td><\/tr>
    Main cause<\/td>A bug in OpenSSL<\/td>The same bug in OpenSSL<\/td><\/tr>
    Affected applications<\/td>Any system running OpenSSL<\/td>MongoDB servers running vulnerable OpenSSL versions<\/td><\/tr>
    Discovered  on (date)<\/td>2014<\/td>2025<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n

    How does MongoBleed work?<\/h2>\n\n\n\n

    To fully understand MongoBleed, it’s first important to know what we\u2018re talking about in the first place. MongoBleed has a CVE ID of 14847 and affects most versions of MongoDB, including community, enterprise, and MongoDB Atlas<\/a>. It also affects installations of MongoDB where a server allows for network compression using zlib<\/a>.<\/p>\n\n\n\n

    In a nutshell, MongoBleed allows an attacker with an access to a MongoDB instance to extract parts of server memory that may contain sensitive data. To exploit the MongoBleed vulnerability, an attacker should:<\/p>\n\n\n

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    1. Ensure that MongoDB is reachable over the Internet.

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    2. Ensure that the targeted server has the zlib compression extension enabled (which it is by default.)<\/li>\n<\/ol>\n<\/div>\n\n\n

      What versions of MongoDB are at risk of a MongoBleed attack?<\/h2>\n\n\n\n

      After identifying that the vulnerability could<\/em> exist, the nefarious party should then ensure that the server is running a vulnerable version of MongoDB. These versions include:<\/p>\n\n\n

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