Phishing for Information: Spearphishing Attachment T1598.002

Tactic: Reconnaissance

Adversaries may send spearphishing messages with a malicious attachment to elicit sensitive information that can be used during targeting. Spearphishing for information is an attempt to trick targets into divulging information, frequently credentials or other actionable information. Spearphishing for information frequently involves social engineering techniques, such as posing as a source with a reason to collect information (ex: Establish Accounts or Compromise Accounts) and/or sending multiple, seemingly urgent messages.

Events covered

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

Authoring guide

Patterns shared across the 2 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 (2 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
CommandLine2contains 2, in 1*\\AppData\\Local\\Microsoft\\Outlook\\*, *\\AppData\\Local\\Temp\\*, *\\Content.Outlook\\*, .htm, :\users\
Image1ends_with 1\brave.exe, \chrome.exe, \firefox.exe

Top indicator values (15 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
.htm
1
CommandLinecontains
.rdp
1
CommandLinecontains
:\users\
16
CommandLinecontains
\downloads\
114
CommandLinein
*\\AppData\\Local\\Microsoft\\Outlook\\*
1
CommandLinein
*\\AppData\\Local\\Temp\\*
12
CommandLinein
*\\Content.Outlook\\*
1
CommandLinein
*\\Downloads\\*
1
CommandLinein
*\\Olk\\Attachments\\*
1
Imageends_with
\brave.exe
111
Imageends_with
\chrome.exe
113
Imageends_with
\firefox.exe
16
Imageends_with
\msedge.exe
114
Imageends_with
\opera.exe
111
Imageends_with
\vivaldi.exe
111

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 1 rule

Splunk 1 rule