Exchange Outbound Connection Timeout must be 10 minutes or less.
Overview
| Finding ID | Version | Rule ID | IA Controls | Severity |
| V-221220 | EX16-ED-000190 | SV-221220r961155_rule | CCI-001095 | medium |
| Description | ||||
| Email system availability depends in part on best practice strategies for setting tuning configurations. This configuration controls the number of idle minutes before the connection is dropped. It works in conjunction with the Maximum Outbound Connections Count setting. Connections, once established, may incur delays in message transfer. The default of 10 minutes is a reasonable window in which to resume activities without maintaining idle connections for excessive intervals. If the timeout period is too long, idle connections may be maintained for unnecessarily long time periods, preventing new connections from being established. Sluggish connectivity increases the risk of lost data. A value of 10 or less is optimal. | ||||
| STIG | Date | |||
| Microsoft Exchange 2016 Edge Transport Server Security Technical Implementation Guide | 2024-12-06 | |||
Related Frameworks
1 mapping across 4 frameworks
Related Frameworks
SCF0 mappings
No source states a mapping between these directly.
Also reachable in 3 hops (2) derived by us, not asserted by any source
Each of these is a route we composed by chaining published mappings. No publisher states a relationship between the two endpoints.
- DISA STIG Benchmark (XCCDF)V2R6intersects(normalised)
- DISA CCI List2025-01-23equal to(normalised)
- SCF Secure Traceability Relationship Mapping (STRM)2026.2intersects
- DISA STIG Benchmark (XCCDF)V2R6intersects(normalised)
- DISA CCI List2025-01-23equal to(normalised)
- SCF Secure Traceability Relationship Mapping (STRM)2026.2intersects
NIST 800-530 mappings
No source states a mapping between these directly.
Also reachable in 2 hops (13) derived by us, not asserted by any source
Each of these is a route we composed by chaining published mappings. No publisher states a relationship between the two endpoints.
- DISA STIG Benchmark (XCCDF)V2R6intersects(normalised)
- DISA STIG Benchmark (XCCDF)V1R1our copyintersects(normalised)
- DISA STIG Benchmark (XCCDF)V1R1intersects(normalised)
- DISA CCI List2025-01-23equal to(normalised)
- DISA STIG Benchmark (XCCDF)V2R6intersects(normalised)
- DISA STIG Benchmark (XCCDF)2our copyintersects(normalised)DISA STIG Benchmark (XCCDF)V2R9our copyintersects(normalised)
- DISA STIG Benchmark (XCCDF)2intersects(normalised)DISA STIG Benchmark (XCCDF)V2R9intersects(normalised)
- DISA CCI List2025-01-23equal to(normalised)
- DISA STIG Benchmark (XCCDF)V2R6intersects(normalised)
- DISA STIG Benchmark (XCCDF)V1R1our copyintersects(normalised)
- DISA STIG Benchmark (XCCDF)V1R1intersects(normalised)
- DISA CCI List2025-01-23equal to(normalised)
- DISA STIG Benchmark (XCCDF)V2R6intersects(normalised)
- DISA STIG Benchmark (XCCDF)V10R7our copyintersects(normalised)
- DISA STIG Benchmark (XCCDF)V10R7intersects(normalised)
- DISA CCI List2025-01-23equal to(normalised)
- DISA STIG Benchmark (XCCDF)V2R6intersects(normalised)
- DISA STIG Benchmark (XCCDF)V1R1our copyintersects(normalised)
- DISA STIG Benchmark (XCCDF)V1R1intersects(normalised)
- DISA CCI List2025-01-23equal to(normalised)
- DISA STIG Benchmark (XCCDF)V2R6intersects(normalised)
- DISA STIG Benchmark (XCCDF)V3R3our copyintersects(normalised)
- DISA STIG Benchmark (XCCDF)V3R3intersects(normalised)
- DISA CCI List2025-01-23equal to(normalised)
- DISA STIG Benchmark (XCCDF)V2R6intersects(normalised)
- DISA STIG Benchmark (XCCDF)1our copyintersects(normalised)
- DISA STIG Benchmark (XCCDF)1intersects(normalised)
- DISA CCI List2025-01-23equal to(normalised)
- DISA STIG Benchmark (XCCDF)V2R6intersects(normalised)
- DISA STIG Benchmark (XCCDF)1our copyintersects(normalised)
- DISA STIG Benchmark (XCCDF)1intersects(normalised)
- DISA CCI List2025-01-23equal to(normalised)
- DISA STIG Benchmark (XCCDF)V2R6intersects(normalised)
- DISA STIG Benchmark (XCCDF)V2R1our copyintersects(normalised)
- DISA STIG Benchmark (XCCDF)V2R1intersects(normalised)
- DISA CCI List2025-01-23equal to(normalised)
- DISA STIG Benchmark (XCCDF)V2R6intersects(normalised)
- DISA STIG Benchmark (XCCDF)V10R7our copyintersects(normalised)
- DISA STIG Benchmark (XCCDF)V10R7intersects(normalised)
- DISA CCI List2025-01-23equal to(normalised)
+3 more (top 10 by confidence shown)
CCI1 mapping
CCI-001095
1.00
- DISA STIG Benchmark (XCCDF)V2R6intersects(normalised)
NIST CSF 2.00 mappings
No source states a mapping between these directly.
Also reachable in 4 hops (1) derived by us, not asserted by any source
Each of these is a route we composed by chaining published mappings. No publisher states a relationship between the two endpoints.
PR.IR-04
0.50
- DISA STIG Benchmark (XCCDF)V2R6intersects(normalised)
- DISA CCI List2025-01-23equal to(normalised)
- SCF Secure Traceability Relationship Mapping (STRM)2026.2intersects
- NIST OLIR Informative ReferenceOLIR 153 (2025-04-07)intersects(normalised)SCF Focal Document mapping (catalog)SCF 2026.2 focalintersects(normalised)
Details
Check Text (C-221220r961155_chk)
Review the Email Domain Security Plan (EDSP).
Determine the Connection Timeout value.
Open the Exchange Management Shell and enter the following command:
Get-SendConnector | Select Name, Identity, ConnectionInactivityTimeOut
For each send connector, if the value of "ConnectionInactivityTimeOut" is not set to "00:10:00", this is a finding.
or
If "ConnectionInactivityTimeOut" is set to other than "00:10:00" and has signoff and risk acceptance in the EDSP, this is not a finding.
Fix Text (F-22924r411787_fix)
Update the EDSP to reflect the Connection Timeout value.
Open the Exchange Management Shell and enter the following command:
Set-SendConnector -Identity <'IdentityName'> -ConnectionInactivityTimeOut 00:10:00
Note: The <IdentityName> value must be in single quotes.
or
The value as identified by the EDSP that has obtained a signoff with risk acceptance.
Repeat the procedure for each send connector.