Browser Information Discovery T1217

Tactic: Discovery

Adversaries may enumerate information about browsers to learn more about compromised environments. Data saved by browsers (such as bookmarks, accounts, and browsing history) may reveal a variety of personal information about users (e.g., banking sites, relationships/interests, social media, etc.) as well as details about internal network resources such as servers, tools/dashboards, or other related infrastructure.

Events covered

3 catalog events are tagged with this technique by at least one rule.

Authoring guide

Patterns shared across the 4 rules above: which fields they filter on, what specific values they look for, and what they exclude. The catalog normalizes field names across vendors so Sigma's Image, Elastic's process.name, and Splunk's process_name collapse into one row. Each rule contributes at most once per row.

Fields filtered most (7 distinct)

The fields most rules look at when detecting this technique. The How column shows the operators authors use (eq, wildcard, regex_match, match) and how often each appears. Sample values are concrete examples to start from, not an exhaustive list.

FieldRulesHowSample values
CommandLine3contains 3-encodedcommand, -s, bookmarks, cookies, cookies.sqlite
Image2ends_with 2\cmd.exe, \where.exe
OriginalFileName2eq 2cmd.exe, where.exe
EfectiveCommand1regex_match 1regexEmpire
EventData1contains 1-encodedcommand, powershell.exe, powershell_ise.exe
EventID1eq 14688
ScriptBlockText1contains 1 -erroraction silentlycontinue, -filter bookmarks, -force

Top indicator values (31 distinct)

Specific (field, operator, value) combinations the rules check for, ranked by how many rules under this technique use each one. The Corpus reach column counts how many rules across the entire catalog (any technique) check the same combination. High numbers point to widely-used indicators that are likely noisy on their own; combine them with another condition for useful signal. Blank means the combination is specific to rules under this technique. Click a value to expand the rules under this technique that use it.

FieldKindValueRules (here)Corpus reach
CommandLinecontains
-encodedcommand
13
CommandLinecontains
-s
110
CommandLinecontains
bookmarks
12
CommandLinecontains
cookies
12
CommandLinecontains
cookies.sqlite
13
CommandLinecontains
dir
18
CommandLinecontains
formhistory.sqlite
1
CommandLinecontains
history
12
CommandLinecontains
key3.db
12
CommandLinecontains
key4.db
12
CommandLinecontains
login data
13
CommandLinecontains
logins.json
12
CommandLinecontains
places.sqlite
12
CommandLinecontains
rmdir
12
CommandLinecontains
sessionstore.jsonlz4
1
EfectiveCommandregex_match
regexEmpire
1
EventDatacontains
-encodedcommand
1
EventDatacontains
powershell.exe
1
EventDatacontains
powershell_ise.exe
1
EventDatacontains
pwsh.exe
1
EventIDeq
4688
1313
Imageends_with
\cmd.exe
1130
Imageends_with
\where.exe
1
OriginalFileNameeq
cmd.exe
165
OriginalFileNameeq
where.exe
1
ScriptBlockTextcontains
-erroraction silentlycontinue
1
ScriptBlockTextcontains
-filter bookmarks
1
ScriptBlockTextcontains
-force
1
ScriptBlockTextcontains
-path
1
ScriptBlockTextcontains
-recurse
12

Exclusions (5 distinct)

Field/operator/value combinations excluded by rules under this technique (top-level not() clauses), sorted by how many rules exclude each. These are the false-positive paths the community has learned to filter out. A new rule that ignores the high-count entries here will likely fire on the same noisy paths. Click a value to expand the rules under this technique that exclude it.

FieldKindValueRules excluding
CommandLinecontains
rmdir
1
EventDatacontains
gc_service.exe
1
EventDatacontains
gc_worker.exe
1
ParentImagecontains
gc_service.exe
1
ParentImagecontains
gc_worker.exe
1

Rules under this technique

Every rule in the catalog tagged with this technique, grouped by vendor. Click a rule title for its full predicates, exclusions, and indicators.

Platform (all)
Domain (all)

Sigma 3 rules

Kusto 1 rule