CVE-2026-81522

Cross-tenant database retargeting via dot/NUL injection in namespace strings in the C++ Driver

HIGH
8.1
CVSS Score
Published: August 27, 2026 at 06:32 PM UTC
Updated: September 29, 2026 at 07:17 PM UTC
1 product affected across 1 vendorC++ Driver

Using C++ Driver by MongoDB?

Get instant alerts when new vulnerabilities affect C++ Driver - before attackers find them.

Real-time alertsTrack your software stackFree plan available
Severity
HIGH8.1
Exploit prediction
EPSS 0.5%
SSVC
No known exploit

Description

A weakness in the MongoDB C++ Driver's handling of caller-supplied namespace identifiers allows special characters embedded in those identifiers. An application that builds a namespace identifier from untrusted input without validating it may therefore have its operation directed at a different target than intended. This can result in limited unauthorized read and write access to data belonging to another logical tenant of the affected application.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

3.0.0 ≤ v < 4.5.13.0.0 ≤ v < 4.5.23.0.0
Affected range stops below 4.5.1, so it looks safe — our inference, not a vendor statement
Affected range stops below 4.5.2, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

Patch and advisory references

References (2)

SSVC — Action Prioritization

SSVCNo known exploitNot automatableTotal impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

8.1HIGHmongodb
Attack Vector
NETWORK
Complexity
LOW
Privileges
LOW
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
HIGH
Integrity
HIGH
Availability
NONE
Vector?

Quick Info

StatusANALYZED
CWE
CWE-116

Get alerted

Stop reading CVE feeds looking for your own stack

Track the products you run and VulnTracker tells you when a new CVE affects them — with what is known about fixing it, and nothing about the rest.

Free plan, no card