CVE-2026-93393
Heap overflow via oversized decrypted TLS record sequence in Windows Secure Channel stream
Published Sep 17, 2026
CVSS 4.0 · 9.2 Critical
EPSS < 1%
KEV · Not listed
Description
A heap-based buffer overflow exists in the TLS transport layer of the MongoDB C Driver when built with the Windows platform TLS backend. A remote endpoint that the client connects to can cause the driver to write uncontrolled data outside the bounds of a heap allocation while processing incoming encrypted traffic after the TLS handshake completes. No authentication or user interaction is required, because the affected processing occurs before any application-level authentication completes. Triggering this issue may lead to memory corruption in the client process, disclosure of adjacent heap memory, or termination of the process.
Affected Products
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CVE record
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NVD configurations
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Red Hat packages
No data
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OpenCVE enrichment
Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).
| Vendor | Product | Default status | Versions | |||||||||||||||||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| MongoDB Inc. | C Driver | unaffected |
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Configuration 1 [-]
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No data.
| Vendor | Product | Versions | ||||||||||||||||||||||||||||||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Mongodb | C Driver |
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Remediation
Tracking
Advisories
Metrics
Attack Vector Network
Attack Complexity High
Privileges Required None
Attack Requirements Present
User Interaction None
Vulnerable System Confidentiality Impact High
Vulnerable System Integrity Impact High
Vulnerable System Availability Impact High
Subsequent System Confidentiality Impact None
Subsequent System Integrity Impact None
Subsequent System Availability Impact None
Attack Vector Network
Attack Complexity High
Privileges Required None
Scope Unchanged
Confidentiality Impact High
Integrity Impact High
Availability Impact High
User Interaction None
No CVSS v3.0
No CVSS v2
This CVE is not in the KEV list.
Exploit prediction score: < 1% (0.468% probability within 30 days)
Exploitation none
Automatable no
Technical Impact total
References
| Link | Providers |
|---|---|
| https://jira.mongodb.org/browse/CDRIVER-6417 |
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History
Sep 29, 2026 7:30 PM
Affected versions updated
View changes
| Type | Values Removed | Values Added |
|---|---|---|
| CPEs | cpe:2.3:a:mongodb:c_driver:*:*:*:*:*:mongodb:*:* |
Sep 18, 2026 9:30 PM
Description updated. Scoring metrics updated
View changes
| Type | Values Removed | Values Added |
|---|---|---|
| Description | A heap-based buffer overflow exists in the TLS transport layer of the MongoDB C Driver when built with the Windows platform TLS backend. A remote endpoint that the client connects to, or an attacker able to impersonate or redirect the client's connection, can cause the driver to write attacker-supplied data outside the bounds of a heap allocation while processing incoming encrypted traffic. No authentication or user interaction is required, because the affected processing occurs before any application-level authentication completes. Successful exploitation may lead to memory corruption in the client process, disclosure of adjacent heap memory, or termination of the process. | A heap-based buffer overflow exists in the TLS transport layer of the MongoDB C Driver when built with the Windows platform TLS backend. A remote endpoint that the client connects to can cause the driver to write uncontrolled data outside the bounds of a heap allocation while processing incoming encrypted traffic after the TLS handshake completes. No authentication or user interaction is required, because the affected processing occurs before any application-level authentication completes. Triggering this issue may lead to memory corruption in the client process, disclosure of adjacent heap memory, or termination of the process. |
| Metrics |
ssvc
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Sep 18, 2026 1:30 PM
First appearance in the feed. Affected vendors updated
View changes
| Type | Values Removed | Values Added |
|---|---|---|
| First Time appeared |
Mongodb
Mongodb c Driver |
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| Vendors & Products |
Mongodb
Mongodb c Driver |
Sep 17, 2026 8:45 PM
Description updated. Title updated. Weaknesses updated. Added references. Scoring metrics updated
View changes
| Type | Values Removed | Values Added |
|---|---|---|
| Description | A heap-based buffer overflow exists in the TLS transport layer of the MongoDB C Driver when built with the Windows platform TLS backend. A remote endpoint that the client connects to, or an attacker able to impersonate or redirect the client's connection, can cause the driver to write attacker-supplied data outside the bounds of a heap allocation while processing incoming encrypted traffic. No authentication or user interaction is required, because the affected processing occurs before any application-level authentication completes. Successful exploitation may lead to memory corruption in the client process, disclosure of adjacent heap memory, or termination of the process. | |
| Title | Heap overflow via oversized decrypted TLS record sequence in Windows Secure Channel stream | |
| Weaknesses | CWE-787 | |
| References |
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| Metrics |
cvssV3_1
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Weaknesses
