Kubernetes Rolebinding Modification

Status: test
Severity: medium
Log source: product kubernetes, service audit
Author: kelnage
Source: github.com/SigmaHQ/sigma

Detects when a Kubernetes Rolebinding is created or modified.

MITRE ATT&CK coverage

Tactic	Techniques
Privilege Escalation	No specific technique

Event coverage

Provider	Event	Title
Kubernetes-clusterrolebindings	create-clusterrolebindings	create clusterrolebindings
Kubernetes-clusterrolebindings	update-clusterrolebindings	update clusterrolebindings
Kubernetes-clusterrolebindings	replace-clusterrolebindings	replace clusterrolebindings
Kubernetes-clusterrolebindings	patch-clusterrolebindings	patch clusterrolebindings
Kubernetes-clusterrolebindings	delete-clusterrolebindings	delete clusterrolebindings
Kubernetes-rolebindings	create-rolebindings	create rolebindings
Kubernetes-rolebindings	update-rolebindings	update rolebindings
Kubernetes-rolebindings	replace-rolebindings	replace rolebindings
Kubernetes-rolebindings	patch-rolebindings	patch rolebindings
Kubernetes-rolebindings	delete-rolebindings	delete rolebindings

Rules detecting the same action

Other rules on this platform that filter on the same API call or operation.

Kubernetes Cluster-Admin Role Binding Created (Elastic)
Kubernetes Creation of a RoleBinding Referencing a ServiceAccount (Elastic)
Kubernetes Service Account Modified RBAC Objects (Elastic)

Rule body yaml

title: Kubernetes Rolebinding Modification
id: 10b97915-ec8d-455f-a815-9a78926585f6
related:
    - id: 0322d9f2-289a-47c2-b5e1-b63c90901a3e
      type: similar
status: test
description: |
    Detects when a Kubernetes Rolebinding is created or modified.
references:
    - https://kubernetes.io/docs/reference/config-api/apiserver-audit.v1/
    - https://medium.com/@seifeddinerajhi/kubernetes-rbac-privilege-escalation-exploits-and-mitigations-26c07629eeab
author: kelnage
date: 2024-07-11
tags:
    - attack.privilege-escalation
logsource:
    product: kubernetes
    service: audit
detection:
    selection:
        objectRef.apiGroup: 'rbac.authorization.k8s.io'
        objectRef.resource:
            - 'clusterrolebindings'
            - 'rolebindings'
        verb:
            - 'create'
            - 'delete'
            - 'patch'
            - 'replace'
            - 'update'
    condition: selection
falsepositives:
    - Modifying a Kubernetes Rolebinding may need to be done by a system administrator.
    - Automated processes may need to take these actions and may need to be filtered.
level: medium

Stages and Predicates

Stage 0: `condition`

selection

Stage 1: `selection`

selection:
    objectRef.apiGroup: 'rbac.authorization.k8s.io'
    objectRef.resource:
        - 'clusterrolebindings'
        - 'rolebindings'
    verb:
        - 'create'
        - 'delete'
        - 'patch'
        - 'replace'
        - 'update'

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
`objectRef.apiGroup`	eq	`rbac.authorization.k8s.io`
`objectRef.resource`	eq	`clusterrolebindings` `rolebindings`
`verb`	eq	`create` `delete` `patch` `replace` `update`

`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)

Kubernetes Rolebinding Modification

MITRE ATT&CK coverage

Event coverage

Rules detecting the same action

Rule body yaml

Stages and Predicates

Stage 0: `condition`

Stage 1: `selection`

Indicators

Keyboard shortcuts

Search operators

Kubernetes Rolebinding Modification

MITRE ATT&CK coverage

Event coverage

Rules detecting the same action

Rule body yaml

Stages and Predicates

Stage 0: condition

Stage 1: selection

Indicators

Stage 0: `condition`

Stage 1: `selection`