BI Connector: Synchronous Access of Remote Resource without Timeout
CVE-2026-81520 is a high-severity synchronous access of remote resource without timeout vulnerability in BI Connector from MongoDB, with a CVSS 3.1 base score of 7.5 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. The record lists version 2.14.31 as the first without the flaw, so updating BI Connector to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.42% chance of exploitation within 30 days, which is low compared with other CVEs.
High severity with no evidence of exploitation so far.
What to do
- Update BI Connector to 2.14.31 or a later version.
- Read the advisory on mongodb.com for workarounds and exact fixed builds.
- Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| MongoDB | BI Connector | before 2.14.31 | 2.14.31 |
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- NetworkCan be exploited remotely over a network, including the internet.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- NoneNo account or login is needed.
- User interaction
- NoneNo action by a victim is required.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- NoneNo data is disclosed.
- Integrity
- NoneNothing can be modified.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H. Scored by CNA (mongodb.com).
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 4.0 | 8.7 | High | CNA (mongodb.com) |
| CVSS 3.1 | 7.5 | High | CNA (mongodb.com) |
Official description
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.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Synchronous Access of Remote Resource without Timeout
The code has a synchronous call to a remote resource, but there is no timeout for the call, or the timeout is set to infinite.
More Synchronous Access of Remote Resource without Timeout vulnerabilities (CWE-1088)
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: yes, technical impact: partial).
- Record last changed materially (score, affected products, status or references).
References
Other vulnerabilities in BI Connector
- 7.5 High severity
- 7.5 High severity
- 7.7 High severity
- 8.0 High severity
- 7.5 High severity
Recent Synchronous Access of Remote Resource without Timeout vulnerabilities
- 7.5 High severity
- 7.5 High severity
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