MongoDB and MongoDB Server Improper Handling of Length Parameter Inconsistency Vulnerability
Exploited since 2025-12-29. No WAF vendor names it yet.
Mismatched length fields in Zlib compressed protocol headers may allow a read of uninitialized heap memory by an unauthenticated client. This issue affects all MongoDB Server v7.0 prior to 7.0.28 versions, MongoDB Server v8.0 versions… More
Mismatched length fields in Zlib compressed protocol headers may allow a read of uninitialized heap memory by an unauthenticated client. This issue affects all MongoDB Server v7.0 prior to 7.0.28 versions, MongoDB Server v8.0 versions prior to 8.0.17, MongoDB Server v8.2 versions prior to 8.2.3, MongoDB Server v6.0 versions prior to 6.0.27, MongoDB Server v5.0 versions prior to 5.0.32, MongoDB Server v4.4 versions prior to 4.4.30, MongoDB Server v4.2 versions greater than or equal to 4.2.0, MongoDB Server v4.0 versions greater than or equal to 4.0.0, and MongoDB Server v3.6 versions greater than or equal to 3.6.0.
Edge coverage
Claimed by vendorsAsk Vigil
AI · answers from this pageWorkers AI (Llama 3.3). Can be wrong: check the cited source.
Severity, decoded
CVSS 4.0Exploitable over the network, with no privileges and no user interaction, leading to full loss of confidentiality.
How the score is built
- Attack vectorAn attacker can reach it over the internet; no access to your network needed.Network
- Attack complexityNo built-in defences have to be bypassed; the attack works reliably.Low
- Attack requirementsThe attack works without any special deployment or timing conditions.None
- Privileges requiredNo account or login is needed.None
- User interactionNo one has to click or open anything; the attack works on its own.None
- Confidentiality impact (vulnerable system)An attacker can read all data the affected component holds, or the most sensitive parts of it.High
- Integrity impact (vulnerable system)Data cannot be changed by the attacker.None
- Availability impact (vulnerable system)The component keeps working normally.None
- Confidentiality impact (other systems)Other systems' data is not exposed.None
- Integrity impact (other systems)Other systems' data cannot be changed.None
- Availability impact (other systems)Other systems keep working normally.None
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:NAttackers are exploiting this in the wild.
Attackers can script the attack end to end and hit many targets at once.
A successful attack gives limited control over the affected software or limited access to its data.
Public exploits
1 found- MetasploitMongoDB Memory Disclosure (CVE-2025-14847) - Mongobleed2025-12-19 · auxiliary · rank Normal · has check
Links are to third-party code: never run it outside an isolated lab.
Timeline
- 2025-12-19CVE publishedCVE List
- 2025-12-19Metasploit module publishedMongoDB Memory Disclosure (CVE-2025-14847) - Mongobleed
- 2025-12-29Added to CISA KEVConfirmed exploitation in the wild
Vendor statements
QuotedCloudflareWAF Managed Rules
We found no public statement from this vendor naming this CVE. That is not proof of no protection: generic rules may still catch it. Each row gives the rule ID and its default action. The feed starts in January 2025, so older rules are missing.
AWSAWS WAF Managed Rules
We found no public statement from this vendor naming this CVE. That is not proof of no protection: generic rules may still catch it. AWS often describes a vulnerability without naming its CVE (for example "Log4j"). We count only entries that name the CVE, so AWS coverage is understated.
Microsoft AzureFront Door and Application Gateway WAF (DRS)
We found no public statement from this vendor naming this CVE. That is not proof of no protection: generic rules may still catch it. The rule tables name CVEs but carry no dates, so Azure is left out of every time-to-rule figure.
Google CloudCloud Armor preconfigured WAF rules
We found no public statement from this vendor naming this CVE. That is not proof of no protection: generic rules may still catch it. Google names few CVEs: the release notes start in May 2024 and the rules reference lists CVEs without dates. Its cve-canary rules are opt-in.
FastlyNext-Gen WAF virtual patches
The CVE predates the oldest entry in this vendor's public feed, so a rule may exist that we cannot see.
F5Attack signatures (Distributed Cloud WAF)
We found no public statement from this vendor naming this CVE. That is not proof of no protection: generic rules may still catch it. Each signature lists the CVEs it references, with its id and date. F5 does not state a default action; signatures enforce once staging ends in your policy.
AkamaiApp & API Protector (Adaptive Security Engine)
This vendor publishes no machine-readable rule changelog we can check.
OWASP CRSCore Rule Set (open source, used inside many WAFs)
We found no public statement from this vendor naming this CVE. That is not proof of no protection: generic rules may still catch it. CRS rarely names CVEs: it relies on generic detections. Our own lab measures what it actually blocks.
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