Credentials from Password Stores: Credentials from Web Browsers T1555.003
Tactic: Credential Access
Adversaries may acquire credentials from web browsers by reading files specific to the target browser. Web browsers commonly save credentials such as website usernames and passwords so that they do not need to be entered manually in the future. Web browsers typically store the credentials in an encrypted format within a credential store; however, methods exist to extract plaintext credentials from web browsers.
Events covered
10 catalog events are tagged with this technique by at least one rule.
| Provider | Event | Title |
|---|---|---|
| Sysmon | Event ID 1 | Process creation |
| Sysmon | Event ID 11 | FileCreate |
| Security-Auditing | Event ID 4656 | A handle to an object was requested. |
| Security-Auditing | Event ID 4663 | An attempt was made to access an object. |
| Security-Auditing | Event ID 4688 | A new process has been created. |
| Security-Auditing | Event ID 5145 | A network share object was checked to see whether client can be granted desired access. |
| ESF | exec | Process Execution (Notify) |
| ESF | open | File Open (NOTIFY) |
| PowerShell | Event ID 4103 | Payload Context: ContextInfo User Data: UserData. |
| PowerShell | Event ID 4104 | Creating Scriptblock text (MessageNumber of MessageTotal). |
Authoring guide
Patterns shared across the 19 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 (28 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.
Top indicator values (167 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.
Exclusions (29 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.
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.
Sigma 8 rules
- Access To Browser Credential Files By Uncommon Applications - Security
- Access to Browser Login Data
- HackTool - WinPwn Execution
- HackTool - WinPwn Execution - ScriptBlock
- Potential Browser Data Stealing
- PUA - WebBrowserPassView Execution
- SQLite Chromium Profile Data DB Access
- User browser credentials dump via network share (DonPapi, Lazagne)
Elastic 3 rules
- Browser Process Spawned from an Unusual Parent
- Keychain Password Retrieval via Command Line
- Suspicious Web Browser Sensitive File Access
Splunk 7 rules
- Browser Credential File Accessed - Windows (Windows Event Log)
- Non Chrome Process Accessing Chrome Default Dir
- Non Firefox Process Access Firefox Profile Dir
- Possible Browser Pass View Parameter
- Stored Credentials from Web Browsers - Windows (PowerShell)
- Windows Credentials from Password Stores Chrome Copied in TEMP Dir
- Windows Credentials from Web Browsers Saved in TEMP Folder