CVE-2026-81529: CWE-88: Improper Neutralization of Argument Delimiters in a Command ('Argument Injection') in MongoDB C# Driver
Description
CVE-2026-81529 is a high-severity vulnerability in the MongoDB C# Driver involving improper neutralization of delimiters in connection-URL construction. This flaw allows a low-privileged user to inject or suppress security-relevant connection options by passing untrusted text that is not properly sanitized. The vulnerability affects specific versions of the driver and could lead to unauthorized modification of connection settings.
CVSS v4.0
Score 7.1high
Affected software
MongoDB
C# Driver
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The MongoDB C# Driver improperly neutralizes argument delimiters when constructing connection URLs. When an application uses the driver's connection-URL builder with untrusted input, the input is serialized without escaping URL or option delimiters. This serialized input is then re-parsed as authoritative connection options, enabling a low-privileged user to inject or suppress connection options that may affect security. The vulnerability is identified as CWE-88 (Improper Neutralization of Argument Delimiters in a Command).
Potential Impact
A low-privileged user can manipulate connection options by injecting or suppressing parameters in the connection URL, potentially altering security-relevant settings. This could lead to unauthorized access or weakening of security controls in applications using the affected MongoDB C# Driver versions.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. No official fix or temporary workaround has been documented at this time.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mongodb
- Date Reserved
- 2026-08-26T22:14:30.340Z
- Cvss Version
- 4.0
- State
- PUBLISHED
Threat ID: 6a909d01acd9273b49b2d3be
Added to database: 08/27/2026, 20:24:33 UTC
Last enriched: 09/08/2026, 10:22:32 UTC
Last updated: 10/10/2026, 18:48:23 UTC
Views: 98
Community Reviews
0 reviewsCrowdsource mitigation strategies, share intel context, and vote on the most helpful responses. Sign in to add your voice and help keep defenders ahead.
Want to contribute mitigation steps or threat intel context? Sign in or create an account to join the community discussion.
Actions
Updates to AI analysis require Pro Console access. Upgrade inside Console → Billing.
Need more coverage?
Upgrade to Pro Console for AI refresh and higher limits.
For incident response and remediation, OffSeq services can help resolve threats faster.
Latest Threats
Check if your credentials are on the dark web
Instant breach scanning across billions of leaked records. Free tier available.