MongoDB BI Connector ODBC driver may write outside an allocated buffer when retrieving large floating point values as character data (CVE-2026-18888) | HOL Guard CVE

Medium · CVSS 6.5CVE-2026-18888

MongoDB BI Connector ODBC driver may write outside an allocated buffer when retrieving large floating point values as character data

Answer in brief

CVE-2026-18888 records a Medium severity (CVSS 6.5) vulnerability in MongoDB BI Connector ODBC driver may write outside an allocated buffer when retrieving large floating point values as character data. The current sources do not mark it as known exploited. The current feed maps MongoDB/BI Connector ODBC Driver (generic). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Aug 12, 2026Updated Sep 11, 2026Source checked Sep 28, 2026First seen by HOL Aug 12, 2026Material review Sep 11, 2026

Upstream Advisory

Key facts

Risk: Medium · CVSS 6.5
Exploitation: Not marked as known exploited
Affected software: 2 mapped packages or products
Fix availability: Available

Why this deserves its current priority

CVSS is 6.5. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps MongoDB/BI Connector ODBC Driver (generic). Check affected ranges and fixed versions before updating.

Affected products and reported versions
Product	Affected versions	Fixed versions
cpe:2.3:a:mongodb:bi_connector_odbc_driver::::::::	Not reported	Not reported

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
MongoDB/BI Connector ODBC Drivergeneric	>=1.0.0 <1.4.9	1.4.9

Recommended response

Check inventory. Check lockfiles and deployed manifests for MongoDB/BI Connector ODBC Driver.
Review the reported fix. Update MongoDB/BI Connector ODBC Driver to 1.4.9 if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

Published upstream
Aug 12, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Sep 11, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Aug 12, 2026

Sources and claim methodology

GitHub security advisorygithub.com

Upstream source description

The MongoDB BI Connector ODBC Driver converts floating point column values into text without checking that the result fits within the destination buffer. When an application reads a sufficiently large floating point value as text, the driver may write beyond the end of that buffer and corrupt adjacent memory. A user who can store data in a collection read through the BI Connector could use this to crash the application performing the read.

Quoted source text, attributed separately from HOL analysis.