7.6
HIGH CVSS 3.1
CVE-2026-18693
Out-of-Bounds Read/Write in MongoDB Timeseries Bucket Handling Leads to Denial of Service and Potential Memory Disclosure
Description

An issue in MongoDB Server's handling of timeseries collections could allow an authenticated user with write privileges to cause an internal data structure to become inconsistent through certain document insertions. A subsequent insert into the affected bucket could then result in the server accessing memory outside its intended bounds, potentially causing a server crash (denial of service), exposure of limited memory contents, or memory corruption.

INFO

Published Date :

Aug. 11, 2026, 7:17 p.m.

Last Modified :

Aug. 11, 2026, 9:17 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-18693 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 134c704f-9b21-4f2e-91b3-4a467353bcc0
CVSS 3.1 HIGH a39b4221-9bd0-4244-95fc-f3e2e07f1deb
CVSS 3.1 HIGH [email protected]
CVSS 3.1 HIGH MITRE-CVE
CVSS 4.0 HIGH a39b4221-9bd0-4244-95fc-f3e2e07f1deb
CVSS 4.0 HIGH [email protected]
Solution
Update MongoDB Server to a non-vulnerable version to prevent data inconsistencies and crashes.
  • Update MongoDB Server to a non-vulnerable version.
  • Apply available security patches from the vendor.
  • Review and sanitize all document insertions.
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-18693.

URL Resource
https://jira.mongodb.org/browse/SERVER-129994
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-18693 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-18693 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-18693 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-18693 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0

    Aug. 11, 2026

    Action Type Old Value New Value
    Added SSVC {'id': 'CVE-2026-18693', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'none'}, {'automatable': 'no'}, {'technicalImpact': 'partial'}], 'version': '2.0.3', 'timestamp': '2026-08-11T20:24:53.628827Z'}
  • New CVE Received by [email protected]

    Aug. 11, 2026

    Action Type Old Value New Value
    Added Affected [{'vendor': 'MongoDB', 'product': 'MongoDB Server', 'versions': [{'status': 'affected', 'version': '8.3.0', 'lessThan': '8.3.8', 'versionType': 'semver'}, {'status': 'affected', 'version': '8.0', 'lessThan': '8.0.29', 'versionType': 'semver'}, {'status': 'affected', 'version': '7.0', 'lessThan': '7.0.40', 'versionType': 'semver'}], 'defaultStatus': 'unaffected'}]
    Added Description An issue in MongoDB Server's handling of timeseries collections could allow an authenticated user with write privileges to cause an internal data structure to become inconsistent through certain document insertions. A subsequent insert into the affected bucket could then result in the server accessing memory outside its intended bounds, potentially causing a server crash (denial of service), exposure of limited memory contents, or memory corruption.
    Added CVSS V4.0 AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
    Added CVSS V3.1 AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:H
    Added CWE CWE-787
    Added Reference https://jira.mongodb.org/browse/SERVER-129994
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.