CVE-2026-81520 (GCVE-0-2026-81520)
Vulnerability from cvelistv5 – Published: 2026-08-28 20:22 – Updated: 2026-08-28 20:22
VLAI
EPSS
VEX
Title
MongoDB Connector for BI Unbounded Authentication Negotiation Leading to Connection Exhaustion
Summary
A network-reachable client that has not yet authenticated can hold a MongoDB Connector for BI authentication session open indefinitely by beginning a SASL-based login exchange and then declining to complete it. Because the negotiation loop had no overall time bound and the read from the client had no deadline, each such session retains a worker, a client connection slot, and its associated backend database connections until the process is restarted. Repeated use of this behavior can consume the configured connection capacity and prevent legitimate users from establishing new sessions.
Severity
CWE
- CWE-1088 - Synchronous Access of Remote Resource without Timeout
Assigner
References
1 reference
Impacted products
1 product
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| MongoDB | BI Connector |
Affected:
0 , < 2.14.31
(semver)
|
guessed |
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"metrics": [
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"description": "CWE-1088: Synchronous Access of Remote Resource without Timeout",
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]
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],
"providerMetadata": {
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"orgId": "a39b4221-9bd0-4244-95fc-f3e2e07f1deb",
"shortName": "mongodb"
},
"references": [
{
"url": "https://www.mongodb.com/docs/bi-connector/current/release-notes/"
}
],
"source": {
"discovery": "INTERNAL"
},
"title": "MongoDB Connector for BI Unbounded Authentication Negotiation Leading to Connection Exhaustion",
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"cveId": "CVE-2026-81520",
"datePublished": "2026-08-28T20:22:42.151Z",
"dateReserved": "2026-08-26T22:10:21.151Z",
"dateUpdated": "2026-08-28T20:22:42.151Z",
"state": "PUBLISHED"
},
"dataType": "CVE_RECORD",
"dataVersion": "5.2",
"vulnerability-lookup:meta": {
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}
}
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Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
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The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the
vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base
model, served locally by ML-Gateway.
They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
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