GitHub Repository Ruleset Modified

Severity: informational
Group by: _document_id
Log types: GitHub.Audit
Tags: GitHub, Defense Evasion, Impair Defenses, Disable or Modify Tools
Reference: https://docs.github.com/en/repositories/configuring-branches-and-merges-in-your-repository/managing-rulesets/about-rulesets
Source: github.com/panther-labs/panther-analysis

Disabling repository ruleset controls could indicate malicious use of admin credentials in an attempt to hide activity.

MITRE ATT&CK coverage

Tactic	Techniques
Stealth	`T1562` Impair Defenses

Rule body yaml

AnalysisType: rule
Filename: github_repo_ruleset_modified.py
RuleID: "GitHub.Repo.RulesetModified"
DisplayName: "GitHub Repository Ruleset Modified"
Enabled: true
LogTypes:
  - GitHub.Audit
Tags:
  - GitHub
  - Defense Evasion
  - Impair Defenses
  - Disable or Modify Tools
Reports:
  MITRE ATT&CK:
    - TA0005:T1562 # Impair Defenses: Disable or Modify Tools
Reference: https://docs.github.com/en/repositories/configuring-branches-and-merges-in-your-repository/managing-rulesets/about-rulesets
Severity: Info
Description: Disabling repository ruleset controls could indicate malicious use of admin credentials in an attempt to hide activity.
DedupPeriodMinutes: 60
Threshold: 1
Runbook: Verify that ruleset modifications are intended and authorized.
Tests:
  - Name: GitHub - Ruleset Created
    ExpectedResult: true
    Log:
      {
        "action": "repository_ruleset.create",
        "actor": "dog",
        "actor_id": "999999999",
        "actor_is_bot": false,
        "actor_location": { "country_code": "US" },
        "business": "bizname",
        "business_id": "12345",
        "created_at": "2024-12-17 00:00:00000000",
        "operation_type": "create",
        "org": "some-org",
        "org_id": 12345678,
        "public_repo": true,
        "repo": "some-org/ruleset-repo",
        "repo_id": 123456789,
        "ruleset_bypass_actors":
          [
            {
              "actor_id": 123456,
              "actor_type": "Integration",
              "bypass_mode": "always",
              "id": 123456,
            },
            {
              "actor_id": 123456,
              "actor_type": "Team",
              "bypass_mode": "always",
              "id": 1234567,
            },
          ],
        "ruleset_conditions":
          [
            {
              "id": 1234567,
              "parameters": { "exclude": [], "include": ["~DEFAULT_BRANCH"] },
              "target": "ref_name",
            },
          ],
        "ruleset_enforcement": "enabled",
        "ruleset_id": "1234567",
        "ruleset_name": "a-ruleset-name",
        "ruleset_rules":
          [
            {
              "id": 12345678,
              "parameters":
                {
                  "allowed_merge_methods": ["merge", "squash", "rebase"],
                  "authorized_dismissal_actors_only": false,
                  "automatic_copilot_code_review_enabled": false,
                  "dismiss_stale_reviews_on_push": false,
                  "ignore_approvals_from_contributors": false,
                  "require_code_owner_review": false,
                  "require_last_push_approval": false,
                  "required_approving_review_count": 1,
                  "required_review_thread_resolution": false,
                  "required_reviewers": [],
                },
              "type": "pull_request",
            },
            { "id": 12345678, "parameters": {}, "type": "deletion" },
            { "id": 12345678, "parameters": {}, "type": "non_fast_forward" },
          ],
        "ruleset_source_type": "Repository",
        "user_agent": "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/131.0.0.0 Safari/537.36",
      }
  - Name: GitHub - Ruleset Deleted
    ExpectedResult: true
    Log:
      {
        "action": "repository_ruleset.destroy",
        "actor": "dog",
        "actor_id": "999999999",
        "actor_is_bot": false,
        "actor_location": { "country_code": "US" },
        "business": "bizname",
        "business_id": "12345",
        "created_at": "2024-12-17 00:00:00000000",
        "operation_type": "remove",
        "org": "some-org",
        "org_id": 12345678,
        "public_repo": false,
        "repo": "some-org/ruleset-repo",
        "repo_id": 123456789,
        "ruleset_bypass_actors":
          [
            {
              "actor_id": 123456,
              "actor_type": "Integration",
              "bypass_mode": "always",
              "id": 123456,
            },
            {
              "actor_id": 123456,
              "actor_type": "Team",
              "bypass_mode": "always",
              "id": 1234567,
            },
          ],
        "ruleset_conditions":
          [
            {
              "id": 1234567,
              "parameters": { "exclude": [], "include": ["~DEFAULT_BRANCH"] },
              "target": "ref_name",
            },
          ],
        "ruleset_enforcement": "enabled",
        "ruleset_id": "1234567",
        "ruleset_name": "a-ruleset-name",
        "ruleset_rules":
          [
            {
              "id": 10994218,
              "parameters":
                {
                  "allowed_merge_methods": ["merge", "squash", "rebase"],
                  "authorized_dismissal_actors_only": false,
                  "automatic_copilot_code_review_enabled": true,
                  "dismiss_stale_reviews_on_push": false,
                  "ignore_approvals_from_contributors": false,
                  "require_code_owner_review": false,
                  "require_last_push_approval": false,
                  "required_approving_review_count": 1,
                  "required_review_thread_resolution": false,
                  "required_reviewers": [],
                },
              "type": "pull_request",
            },
            { "id": 10994219, "parameters": {}, "type": "deletion" },
            { "id": 10994220, "parameters": {}, "type": "non_fast_forward" },
          ],
        "ruleset_source_type": "Repository",
        "user_agent": "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/131.0.0.0 Safari/537.36",
      }

  - Name: GitHub - Non Webhook Event
    ExpectedResult: false
    Log:
      {
        "actor": "cat",
        "action": "org.invite_member",
        "org": "my-org",
        "p_log_type": "GitHub.Audit",
        "repo": "my-org/my-repo",
      }
  - Name: Github - Ruleset Modified
    ExpectedResult: true
    Log:
      {
        "action": "repository_ruleset.update",
        "actor": "dog",
        "actor_id": "999999999",
        "actor_is_bot": false,
        "actor_location": { "country_code": "US" },
        "business": "bizname",
        "business_id": "12345",
        "created_at": "2024-12-17 00:00:00000000",
        "operation_type": "modify",
        "org": "some-org",
        "org_id": 12345678,
        "public_repo": false,
        "repo": "some-org/ruleset-repo",
        "repo_id": 123456789,
        "ruleset_bypass_actors":
          [
            {
              "actor_id": 123456,
              "actor_type": "Integration",
              "bypass_mode": "always",
              "id": 123456,
            },
            {
              "actor_id": 123456,
              "actor_type": "Team",
              "bypass_mode": "always",
              "id": 1234567,
            },
          ],
        "ruleset_conditions":
          [
            {
              "id": 1234567,
              "parameters": { "exclude": [], "include": ["~DEFAULT_BRANCH"] },
              "target": "ref_name",
            },
          ],
        "ruleset_enforcement": "enabled",
        "ruleset_id": "1234567",
        "ruleset_name": "a-ruleset-name",
        "ruleset_rules_updated":
          [
            {
              "id": 12345678,
              "old_parameters":
                {
                  "allowed_merge_methods": ["merge", "squash", "rebase"],
                  "authorized_dismissal_actors_only": false,
                  "automatic_copilot_code_review_enabled": false,
                  "dismiss_stale_reviews_on_push": false,
                  "ignore_approvals_from_contributors": false,
                  "require_code_owner_review": false,
                  "require_last_push_approval": false,
                  "required_approving_review_count": 1,
                  "required_review_thread_resolution": false,
                  "required_reviewers": [],
                },
              "parameters":
                {
                  "allowed_merge_methods": ["merge", "squash", "rebase"],
                  "authorized_dismissal_actors_only": false,
                  "automatic_copilot_code_review_enabled": true,
                  "dismiss_stale_reviews_on_push": false,
                  "ignore_approvals_from_contributors": false,
                  "require_code_owner_review": false,
                  "require_last_push_approval": false,
                  "required_approving_review_count": 1,
                  "required_review_thread_resolution": false,
                  "required_reviewers": [],
                },
              "type": "pull_request",
            },
          ],
        "ruleset_source_type": "Repository",
        "user_agent": "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/131.0.0.0 Safari/537.36",
      }
  - Name: Github - Ruleset Modified for entire Organization
    ExpectedResult: true
    Log:
      {
        "action": "repository_ruleset.update",
        "actor": "dog",
        "actor_id": "999999999",
        "actor_is_bot": false,
        "actor_location": { "country_code": "US" },
        "business": "bizname",
        "business_id": "12345",
        "created_at": "2024-12-17 00:00:00000000",
        "operation_type": "modify",
        "org": "some-org",
        "org_id": 12345678,
        "ruleset_enforcement": "disabled",
        "ruleset_id": "1082915",
        "ruleset_name": "Name of org-wide ruleset",
        "ruleset_old_enforcement": "evaluate",
        "ruleset_source_type": "Organization",
        "user_agent": "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/132.0.0.0 Safari/537.36",
      }

Detection logic

Condition

action starts_with "repository_ruleset."

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
`action`	starts_with	`repository_ruleset.`

Output fields

Fields the rule emits when it matches. Chronicle authors list these in the outcome block; they appear on the detection and $risk_score drives alerting. Sentinel / Defender XDR rules build them up through project / summarize / extend stages. Sentinel maps these into alert fields via entityMappings and customDetails; Defender XDR custom detections surface them as alert fields directly.

Field	Source
`action`
`actor`
`actor_location`	`actor_location.country_code`
`org`
`repo`
`user`

`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)