Clipboard Collection with Xclip Tool

Status: test
Severity: low
Log source: product linux, category process_creation
Author: Pawel Mazur, Roberto Rodriguez (Cyb3rWard0g), OTR (Open Threat Research), MSTIC
Source: github.com/SigmaHQ/sigma

Detects attempts to collect data stored in the clipboard from users with the usage of xclip tool. Xclip has to be installed. Highly recommended using rule on servers, due to high usage of clipboard utilities on user workstations.

MITRE ATT&CK coverage

Tactic	Techniques
Collection	`T1115` Clipboard Data

Event coverage

Provider	Event
Sysmon-for-Linux	Event ID 1

Rule body yaml

title: Clipboard Collection with Xclip Tool
id: ec127035-a636-4b9a-8555-0efd4e59f316
status: test
description: |
    Detects attempts to collect data stored in the clipboard from users with the usage of xclip tool. Xclip has to be installed.
    Highly recommended using rule on servers, due to high usage of clipboard utilities on user workstations.
references:
    - https://www.packetlabs.net/posts/clipboard-data-security/
author: Pawel Mazur, Roberto Rodriguez (Cyb3rWard0g), OTR (Open Threat Research), MSTIC
date: 2021-10-15
modified: 2022-09-15
tags:
    - attack.collection
    - attack.t1115
logsource:
    product: linux
    category: process_creation
detection:
    selection:
        Image|contains: 'xclip'
        CommandLine|contains|all:
            - '-sel'
            - 'clip'
            - '-o'
    condition: selection
falsepositives:
    - Legitimate usage of xclip tools.
level: low

Stages and Predicates

Stage 0: `condition`

selection

Stage 1: `selection`

selection:
    Image|contains: 'xclip'
    CommandLine|contains|all:
        - '-sel'
        - 'clip'
        - '-o'

Indicators

Each row is a field, operator, and value that the rule matches. The corpus column counts how many other rules in the catalog look for the same combination: high numbers point to widely-used, community-vetted indicators. Blank or 1 shows that the indicator is specific to this rule.

Field	Kind	Values
`CommandLine`	match	`-o` `-sel` `clip`
`Image`	match	`xclip`

`j` / `k`	Scroll down / up
`d` / `u`	Half-page down / up
`gg` / `G`	Top / bottom
`h` / `l`	History back / forward
`f`	Follow link (`Shift` = new tab)
`/`	Focus search
`?`	Toggle this help
`↑` / `↓`	Navigate search results
`Enter`	Open highlighted result
`Esc`	Close results / dialog

`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)

Clipboard Collection with Xclip Tool

MITRE ATT&CK coverage

Event coverage

Rule body yaml

Stages and Predicates

Stage 0: `condition`

Stage 1: `selection`

Indicators

Keyboard shortcuts

Search operators

Clipboard Collection with Xclip Tool

MITRE ATT&CK coverage

Event coverage

Rule body yaml

Stages and Predicates

Stage 0: condition

Stage 1: selection

Indicators

Stage 0: `condition`

Stage 1: `selection`