Regular expression injection via unescaped characters in LINQ query translation in MongoDB C# Driver (CVE-2026-88026) | HOL Guard CVE

Unknown severity · Source severity not reportedCVE-2026-88026

Regular expression injection via unescaped characters in LINQ query translation in MongoDB C# Driver

Answer in brief

CVE-2026-88026 records a Unknown severity vulnerability in Regular expression injection via unescaped characters in LINQ query translation in MongoDB C# Driver. The current sources do not mark it as known exploited. The current feed maps MongoDB/C# 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 Sep 10, 2026Updated Sep 10, 2026Source checked Sep 10, 2026First seen by HOL Sep 10, 2026Material review Sep 10, 2026

Upstream Advisory

Key facts

Risk: Unknown severitySource severity not reported
Exploitation: Not marked as known exploited
Affected software: 1 mapped package or product
Fix availability: Not reported

Why this deserves its current priority

A CVSS score is not reported in the current record. 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/C# Driver (generic). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
MongoDB/C# Drivergeneric	2.14.0	Not reported

Recommended response

Check inventory. Check lockfiles and deployed manifests for MongoDB/C# Driver.
Review the reported fix. Monitor this advisory for an available fix and review any installs of the affected package.

Evidence timeline and material changes

Published upstream
Sep 10, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Sep 10, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Sep 10, 2026

Sources and claim methodology

Source referencejira.mongodb.org

Upstream source description

Improper neutralization of regular-expression metacharacters in the LINQ query translation component of the MongoDB C# Driver can cause a caller-supplied character sequence to alter a regular-expression predicate generated by an affected application. An authenticated user who can influence such a value may cause the application to return records beyond those intended by the original filter.

Quoted source text, attributed separately from HOL analysis.