Git Argument Injection in prefecthq/prefect

Prefect version 3.6.23 is vulnerable to remote code execution due to improper handling of user-controlled input in the `GitRepository` storage class. The `commit_sha` parameter, which is passed to git commands, lacks validation and does not include a `--` separator to distinguish user input from git flags. This allows attackers to inject arbitrary git flags, such as `--upload-pack`, enabling execution of external programs. Additionally, the `directories` parameter can be exploited to inject git flags during sparse-checkout operations. These vulnerabilities allow any user with deployment creation permissions to execute arbitrary commands on worker machines, compromising shared work pools in multi-tenant environments.

Problem type

CWE-94 Improper Control of Generation of Code

Affected products

prefecthq

prefecthq/prefect

<= latest - AFFECTED

References

huntr.com

https://huntr.com/bounties/e2e88a0f-a8f6-49c9-94c5-e98dc385f07a

JSON source

https://cveawg.mitre.org/api/cve/CVE-2026-5366

Click to expand

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  "dataVersion": "5.2",
  "cveMetadata": {
    "cveId": "CVE-2026-5366",
    "assignerOrgId": "c09c270a-b464-47c1-9133-acb35b22c19a",
    "assignerShortName": "@huntr_ai",
    "dateUpdated": "2026-06-20T16:43:37.345Z",
    "dateReserved": "2026-04-01T18:18:27.682Z",
    "datePublished": "2026-06-20T16:43:37.345Z",
    "state": "PUBLISHED"
  },
  "containers": {
    "cna": {
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        "orgId": "c09c270a-b464-47c1-9133-acb35b22c19a",
        "shortName": "@huntr_ai",
        "dateUpdated": "2026-06-20T16:43:37.345Z"
      },
      "title": "Git Argument Injection in prefecthq/prefect",
      "descriptions": [
        {
          "lang": "en",
          "value": "Prefect version 3.6.23 is vulnerable to remote code execution due to improper handling of user-controlled input in the `GitRepository` storage class. The `commit_sha` parameter, which is passed to git commands, lacks validation and does not include a `--` separator to distinguish user input from git flags. This allows attackers to inject arbitrary git flags, such as `--upload-pack`, enabling execution of external programs. Additionally, the `directories` parameter can be exploited to inject git flags during sparse-checkout operations. These vulnerabilities allow any user with deployment creation permissions to execute arbitrary commands on worker machines, compromising shared work pools in multi-tenant environments."
        }
      ],
      "affected": [
        {
          "vendor": "prefecthq",
          "product": "prefecthq/prefect",
          "versions": [
            {
              "version": "unspecified",
              "status": "affected",
              "versionType": "custom",
              "lessThanOrEqual": "latest"
            }
          ]
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "lang": "en",
              "description": "CWE-94 Improper Control of Generation of Code",
              "cweId": "CWE-94",
              "type": "CWE"
            }
          ]
        }
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      "references": [
        {
          "url": "https://huntr.com/bounties/e2e88a0f-a8f6-49c9-94c5-e98dc385f07a"
        }
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      "metrics": [
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          "cvssV3_0": {
            "version": "3.0",
            "vectorString": "CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H",
            "attackVector": "NETWORK",
            "attackComplexity": "LOW",
            "privilegesRequired": "LOW",
            "userInteraction": "NONE",
            "scope": "CHANGED",
            "confidentialityImpact": "HIGH",
            "integrityImpact": "HIGH",
            "availabilityImpact": "HIGH",
            "baseScore": 9.9,
            "baseSeverity": "CRITICAL"
          }
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}