Microsoft-Windows-DFSN-ServerFilter

12 events across 2 channels

Event	Title	Channel	Sample
1	GetReferral Request is received by the DFSN-ServerFilter from SRV.	Analytic	N
1	GetReferral Request is received by the DFSN-ServerFilter from SRV	Operational	N
2	GetReferral Request has been inserted into the Upcall queue and pending …	Analytic	N
2	GetReferral Request has been inserted into the Upcall queue and pending …	Operational	N
3	GetReferral Response is ready to be returned to SRV.	Analytic	N
3	GetReferral Response is ready to be returned to SRV	Operational	N
4	ProcessUpcall is started by DFSN-ServerService and ready to post response to the …	Analytic	N
4	ProcessUpcall is started by DFSN-ServerService and ready to post response to the …	Operational	N
5	ProcessUpcall has posted the response to the pending Upcall request in …	Analytic	N
5	ProcessUpcall has posted the response to the pending Upcall request in …	Operational	N
6	ProcessUpcall has dequeued an Upcall request and ready to return to …	Analytic	N
6	ProcessUpcall has dequeued an Upcall request and ready to return to …	Operational	N

Event ID 1: GetReferral Request is received by the DFSN-ServerFilter from SRV.

Provider: Microsoft-Windows-DFSN-ServerFilter
Channel: Analytic
Task: GetReferral
Opcode: RequestReceived

Description

GetReferral Request is received by the DFSN-ServerFilter from SRV.sys.

Message #

GetReferral Request is received by the DFSN-ServerFilter from SRV.sys

Fields #

Name	Description
`InputBuffer` Pointer
`Request` Pointer
`InputBufferLength` UInt16
`RequestSize` UInt16

Event ID 1: GetReferral Request is received by the DFSN-ServerFilter from SRV

Provider: Microsoft-Windows-DFSN-ServerFilter
Channel: Operational
Task: GetReferral
Opcode: RequestReceived

Description

GetReferral Request is received by the DFSN-ServerFilter from SRV.sys.

Fields #

Name	Description
`InputBuffer` Pointer
`Request` Pointer
`InputBufferLength` UInt16
`RequestSize` UInt16

Event ID 2: GetReferral Request has been inserted into the Upcall queue and pending processing by the DFSN-ServerService

Provider: Microsoft-Windows-DFSN-ServerFilter
Channel: Analytic
Task: GetReferral
Opcode: Queued

Description

GetReferral Request has been inserted into the Upcall queue and pending processing by the DFSN-ServerService.

Message #

GetReferral Request has been inserted into the Upcall queue and pending processing by the DFSN-ServerService

Fields #

Name	Description
`Request` Pointer

Event ID 2: GetReferral Request has been inserted into the Upcall queue and pending processing by the DFSN-ServerService

Provider: Microsoft-Windows-DFSN-ServerFilter
Channel: Operational
Task: GetReferral
Opcode: Queued

Description

GetReferral Request has been inserted into the Upcall queue and pending processing by the DFSN-ServerService.

Fields #

Name	Description
`Request` Pointer

Event ID 3: GetReferral Response is ready to be returned to SRV.

Provider: Microsoft-Windows-DFSN-ServerFilter
Channel: Analytic
Task: GetReferral
Opcode: ResponseReady

Description

GetReferral Response is ready to be returned to SRV.sys by the DFSN-ServerFilter.

Message #

GetReferral Response is ready to be returned to SRV.sys by the DFSN-ServerFilter

Fields #

Name	Description
`Request` Pointer
`OutputBuffer` Pointer
`RequestSize` UInt16
`OutputBufferLength` UInt16
`Status` UInt32	NTSTATUS reference

Event ID 3: GetReferral Response is ready to be returned to SRV

Provider: Microsoft-Windows-DFSN-ServerFilter
Channel: Operational
Task: GetReferral
Opcode: ResponseReady

Description

GetReferral Response is ready to be returned to SRV.sys by the DFSN-ServerFilter.

Fields #

Name	Description
`Request` Pointer
`OutputBuffer` Pointer
`RequestSize` UInt16
`OutputBufferLength` UInt16
`Status` UInt32	NTSTATUS reference

Event ID 4: ProcessUpcall is started by DFSN-ServerService and ready to post response to the request it just processed in DFSN-ServerFilter

Provider: Microsoft-Windows-DFSN-ServerFilter
Channel: Analytic
Task: ProcessUpcall
Opcode: Start

Description

ProcessUpcall is started by DFSN-ServerService and ready to post response to the request it just processed in DFSN-ServerFilter.

Message #

ProcessUpcall is started by DFSN-ServerService and ready to post response to the request it just processed in DFSN-ServerFilter

Fields #

Name	Description
`ResponseBuffer` Pointer
`Request` Pointer
`ResponseBufferLength` UInt16
`RequestSize` UInt16

Event ID 4: ProcessUpcall is started by DFSN-ServerService and ready to post response to the request it just processed in DFSN-ServerFilter

Provider: Microsoft-Windows-DFSN-ServerFilter
Channel: Operational
Task: ProcessUpcall
Opcode: Start

Description

ProcessUpcall is started by DFSN-ServerService and ready to post response to the request it just processed in DFSN-ServerFilter.

Fields #

Name	Description
`ResponseBuffer` Pointer
`Request` Pointer
`ResponseBufferLength` UInt16
`RequestSize` UInt16

Event ID 5: ProcessUpcall has posted the response to the pending Upcall request in DFSN-ServerFilter

Provider: Microsoft-Windows-DFSN-ServerFilter
Channel: Analytic
Task: ProcessUpcall
Opcode: ResponsePosted

Description

ProcessUpcall has posted the response to the pending Upcall request in DFSN-ServerFilter.

Message #

ProcessUpcall has posted the response to the pending Upcall request in DFSN-ServerFilter

Fields #

Name	Description
`Response` Pointer
`Status` UInt32	NTSTATUS reference

Event ID 5: ProcessUpcall has posted the response to the pending Upcall request in DFSN-ServerFilter

Provider: Microsoft-Windows-DFSN-ServerFilter
Channel: Operational
Task: ProcessUpcall
Opcode: ResponsePosted

Description

ProcessUpcall has posted the response to the pending Upcall request in DFSN-ServerFilter.

Fields #

Name	Description
`Response` Pointer
`Status` UInt32	NTSTATUS reference

Event ID 6: ProcessUpcall has dequeued an Upcall request and ready to return to DFSN-ServerService to process the request

Provider: Microsoft-Windows-DFSN-ServerFilter
Channel: Analytic
Task: ProcessUpcall
Opcode: RequestDequeued

Description

ProcessUpcall has dequeued an Upcall request and ready to return to DFSN-ServerService to process the request.

Message #

ProcessUpcall has dequeued an Upcall request and ready to return to DFSN-ServerService to process the request

Fields #

Name	Description
`Request` Pointer
`OutputBuffer` Pointer
`RequestSize` UInt16
`OutputBufferLength` UInt16
`Status` UInt32	NTSTATUS reference

Event ID 6: ProcessUpcall has dequeued an Upcall request and ready to return to DFSN-ServerService to process the request

Provider: Microsoft-Windows-DFSN-ServerFilter
Channel: Operational
Task: ProcessUpcall
Opcode: RequestDequeued

Description

ProcessUpcall has dequeued an Upcall request and ready to return to DFSN-ServerService to process the request.

Fields #

Name	Description
`Request` Pointer
`OutputBuffer` Pointer
`RequestSize` UInt16
`OutputBufferLength` UInt16
`Status` UInt32	NTSTATUS reference

Provenance

Where this provider's schema came from, and which Windows build it was observed on. Windows can change a provider's event schema between builds, so use this to judge whether it matches the build you collect from.

ETW provider GUID 5407baea-a563-4e56-819f-7deaa72807ce

Defined in dfs.sys, the binary that emits these events.

Observed on:

WS2022-20348.4893, schema read from the registered manifest, binary version 10.0.20348.1, captured 2026-06-02

Downloads

Microsoft-Windows-DFSN-ServerFilter registered manifest XML (in the WS2022-20348.4893 manifest pack, 1.9 MB) manifest-xml

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`type:`	`events` / `rules` / `providers`
`vendor:`	`sigma` / `elastic` / `splunk` / `kusto` / `chronicle` (vendor name alone also works: `sigma:`, `kql:`, `secops:`…)
`tactic:`	TA-id, slug, or name: `credential_access`, `TA0006`
`technique:`	technique or sub-technique ID: `T1003`, `T1003.001` (alias `tech:`)
`severity:`	`critical` / `high` / `medium` / `low` / `informational` (alias `sev:`)
`risk_score`	Numeric comparison on the Elastic risk score (0 to 100): `risk_score>50`, `risk_score<=20`, `risk_score=99` (alias `risk`; Elastic rules only)
`stages:`	Rules with exactly N pipeline stages
`correlation:`	`single_event` / `sequence` / `alternatives` / `alternatives_cross_log` / `all_required` / `correlated`
`with:`	Co-occurrence event-id; stacks (`with:4624 with:4769`) to require all, while a comma list in one occurrence (`with:4624,4769`) is an either-or group. Implies multi-event
`like:`	Structural neighbors of a rule slug (equivalents + subsumption stricter / broader): `like:comsvcs_lsass_memory_dump-splunk-sysmon`
`groupby:`	Entity-grouping substring match against `group_by_keys`: `groupby:user`, `groupby:host`
`uses:`	Rules whose predicate tree touches the field (any kind, any value): `uses:CommandLine`
`excludes:`	Rules with top-level `not()` clauses on the field (FP whitelists): `excludes:ParentImage`
`field:` / `value:`	Predicate search; narrows rule cards to those with a matching leaf and drives the indicator tier. Unquoted = substring, wildcards allowed (`value:mimikatz`)
`indicator:`	Shorthand for `field:F value:V`: `indicator:Image=*\powershell.exe`
`kind:`	Filter by predicate kind. Narrows rule cards to those carrying a matching predicate leaf (`vendor:elastic kind:cidr_match`) and drives the indicator tier: `contains` / `starts_with` / `ends_with` / `regex` / `cidr` / `eq` / `in` … (operator aliases `op:`/`match:`)
`has:` / `no:`	`sample`, `field`, `notes`, `refs`, `trace`, `thirdparty`, `rule`, `pattern`, `timewindow`, `threshold`, `newterms`, `sigma`/`elastic`/`splunk`/`kusto`/`chronicle`
`-op:val`	Exclude matches; works on most operators but not `type:`/`like:`/`has:`/`no:` (use `no:<flag>` to exclude a rule flag): `tactic:execution -vendor:splunk`. Standalone `-kind:`/`-field:`/`-value:` drop every rule carrying a matching predicate leaf (`type:rules -kind:is_null`)
`field:"…"` / `value:"…"`	Quoted value = anchored exact match (also allows spaces): `value:"net user"`
`a,b`	Comma = OR inside one operator (`vendor:sigma,elastic`, `severity:high,critical`); repeating a facet merges the same way. `field:`/`value:` never split (literal commas)
`vendors:` / `stage:`	Singular and plural spellings fold to the canonical operator and value: `tactics:` = `tactic:`, `type:event` = `type:events`, `correlation:sequences` = `correlation:sequence`, `has:thresholds` = `has:threshold`
`"quoted phrase"`	Exact-match a multi-word phrase (free text)