CVE-2026-82066Network attack vector

Heap disclosure via mis-indexed query-planner tie-break vectors

Published Sep 8, 2026 · Updated Sep 8, 2026

Heap out-of-bounds read in MongoDB Server allows remote authenticated users to disclose heap memory through crafted query operations. The query multi-planner mis-indexes tie-break vectors, causing reads past allocated heap buffers whose bytes can enter diagnostic query statistics. Database read and write privileges are required, and only partial heap contents are observable through that diagnostic output.

CVSS severity5.3
Medium
EPSS probability0.21%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Heap out-of-bounds read in MongoDB Server allows remote authenticated users to disclose heap memory through crafted query operations. The query multi-planner mis-indexes tie-break vectors, causing reads past allocated heap buffers whose bytes can enter diagnostic query statistics. Database read and write privileges are required, and only partial heap contents are observable through that diagnostic output.

The record

CVE
CVE-2026-82066
Published
Sep 8, 2026
Updated
Sep 8, 2026
Vendor
MongoDB
Product
MongoDB Server
Classifications
CWE-125, T1005
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Sep 8, 2026CVE publishedPublication date reported by the CVE source.
  2. Sep 8, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=7.0.0 <7.0.41
  2. Affected versionversion=8.0.0 <8.0.30
  3. Affected versionversion=8.3.0 <8.3.9

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

MongoDB · MongoDB Serverversion=7.0.0 <7.0.41; version=8.0.0 <8.0.30; version=8.3.0 <8.3.9

Published CVSS scores

4.3MongoDBCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N
5.3MongoDBCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-125Out-of-bounds Read
T1005Data from Local System

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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