{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "extracted_events": [
              {
                "introduced": "0"
              },
              {
                "fixed": "1.2.1"
              }
            ],
            "source": [
              "AFFECTED_FIELD",
              "REFERENCES"
            ]
          },
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "0107ac6a4575ea200d0b92287ea58f975be9505d"
            },
            {
              "fixed": "59e255c49c920fd6b67471ab9ef3bf194439a3f2"
            },
            {
              "fixed": "401bde09ac47fb11375ecf9fb663970532995776"
            }
          ],
          "repo": "https://github.com/wktk/conflibot",
          "type": "GIT"
        }
      ]
    }
  ],
  "aliases": [
    "GHSA-2qvg-qr73-mqxp"
  ],
  "database_specific": {
    "cna_assigner": "GitHub_M",
    "cwe_ids": [
      "CWE-78"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/55xxx/CVE-2026-55158.json"
  },
  "details": "Conflibot warns in advance when merging a pull request will cause conflicts in other open pull requests. Prior to 1.2.1, src/index.ts builds git checkout, git merge, and git format-patch commands by interpolating the attacker-controlled pull request head.ref value into strings passed to exec. In the documented pull_request_target configuration, an attacker can open a pull request, including from a fork, whose branch name contains shell metacharacters, and the workflow automatically interprets those characters as commands without maintainer interaction. The commands execute on a runner with base-repository secrets and a write-scoped GITHUB_TOKEN, allowing arbitrary command execution, secret or token exfiltration, unauthorized pushes, and other token abuse. The fixed implementations in src/index.ts and src/conflibot.ts use execFile or spawn argument arrays, and the v2 line also uses numeric pull-request refs rather than branch names. This issue is fixed in versions 1.2.1 and 2.0.0.",
  "id": "CVE-2026-55158",
  "modified": "2026-09-19T03:30:42.685396219Z",
  "published": "2026-09-15T14:47:58.804Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/wktk/conflibot/releases/tag/v1.2.1"
    },
    {
      "type": "WEB",
      "url": "https://github.com/wktk/conflibot/releases/tag/v2.0.0"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/55xxx/CVE-2026-55158.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/wktk/conflibot/security/advisories/GHSA-2qvg-qr73-mqxp"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-55158"
    },
    {
      "type": "FIX",
      "url": "https://github.com/wktk/conflibot/commit/0107ac6a4575ea200d0b92287ea58f975be9505d"
    },
    {
      "type": "FIX",
      "url": "https://github.com/wktk/conflibot/commit/59e255c49c920fd6b67471ab9ef3bf194439a3f2"
    },
    {
      "type": "FIX",
      "url": "https://github.com/wktk/conflibot/pull/329"
    }
  ],
  "schema_version": "1.9.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Conflibot: Command injection via crafted pull request branch names under pull_request_target"
}