Silverstripe Advanced Workflow: Remote code execution via advanced workflow email template

{
  "id": "0cf583ecc0c1e580275b067a74d65e1ea39460e1f15ad9f5de094dd2fb96b1d0",
  "url": "https://osv.dev/vulnerability/CVE-2026-54718",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "Silverstripe Advanced Workflow: Remote code execution via advanced workflow email template",
    "summary": "Silverstripe Advanced Workflow is a highly configurable step-based workflow module. Prior to 6.4.5, 7.1.3, and 7.2.1, an attacker with permission to author the advanced workflow email template can place a specially crafted server-side template payload in NotifyUsersWorkflowAction.EmailTemplate. When NotifyUsersWorkflowAction renders the field through the Silverstripe template engine SSTemplateParser, the payload can cause PHP evaluation and arbitrary code execution on the server; the regression coverage is in tests/php/WorkflowEngineTest.php. This issue is fixed in versions 6.4.5, 7.1.3, and 7.2.1.",
    "evidence": "osv:CVE-2026-54718",
    "products": [],
    "severity": "high",
    "structured": {
      "id": "CVE-2026-54718",
      "aliases": [
        "CVE-2026-54718",
        "GHSA-39mm-rwm3-29jp"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/silverstripe/silverstripe-advancedworkflow",
              "type": "GIT",
              "events": [
                {
                  "introduced": "0"
                },
                {
                  "fixed": "f170766af992ed2ed3e5f21d127d0d0d3129678b"
                },
                {
                  "introduced": "c40d774ccec59872dc95fc2d95a4365db3afdc18"
                },
                {
                  "fixed": "28d0b536491e5c68b1c445579bdd1ddc8beaf8bb"
                },
                {
                  "introduced": "063cd839c6c0204eac743b2eefb78f1585eea766"
                },
                {
                  "fixed": "8c4570aa115d97e8175968bf39020efdee60effc"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "range": [
                      {
                        "introduced": "0"
                      },
                      {
                        "fixed": "6.4.5"
                      }
                    ],
                    "source": "AFFECTED_FIELD",
                    "strategy": "StringRangeExpression"
                  },
                  {
                    "range": [
                      {
                        "introduced": "7.0.0"
                      },
                      {
                        "fixed": "7.1.3"
                      }
                    ],
                    "source": "AFFECTED_FIELD",
                    "strategy": "StringRangeExpression"
                  },
                  {
                    "range": [
                      {
                        "introduced": "7.2.0"
                      },
                      {
                        "fixed": "7.2.1"
                      }
                    ],
                    "source": "AFFECTED_FIELD",
                    "strategy": "StringRangeExpression"
                  },
                  {
                    "range": [
                      {
                        "fixed": "28d0b536491e5c68b1c445579bdd1ddc8beaf8bb"
                      }
                    ],
                    "source": "REFERENCES_COMMIT"
                  },
                  {
                    "range": [
                      {
                        "fixed": "f170766af992ed2ed3e5f21d127d0d0d3129678b"
                      }
                    ],
                    "source": "REFERENCES_COMMIT"
                  },
                  {
                    "range": [
                      {
                        "fixed": "f170766af992ed2ed3e5f21d127d0d0d3129678b"
                      }
                    ],
                    "source": "REFERENCES_TAG",
                    "original_tag": "6.4.5"
                  },
                  {
                    "range": [
                      {
                        "fixed": "28d0b536491e5c68b1c445579bdd1ddc8beaf8bb"
                      }
                    ],
                    "source": "REFERENCES_TAG",
                    "original_tag": "7.1.3"
                  },
                  {
                    "range": [
                      {
                        "fixed": "8c4570aa115d97e8175968bf39020efdee60effc"
                      }
                    ],
                    "source": "REFERENCES_TAG",
                    "original_tag": "7.2.1"
                  }
                ]
              }
            }
          ],
          "versions": [
            "7.2.0-rc1",
            "7.2.0-beta1",
            "7.2.0",
            "6.4.4",
            "7.1.2",
            "6.4.3",
            "7.1.1",
            "7.1.0-rc1",
            "7.1.0",
            "6.4.2",
            "7.1.0-beta1",
            "6.4.1",
            "6.4.0",
            "6.4.0-rc1",
            "6.4.0-beta1",
            "7.0.0-alpha1",
            "6.3.0-rc1",
            "6.3.0-beta1",
            "6.3.0",
            "6.2.0-beta1",
            "6.1.0-beta1",
            "6.0.0-beta1",
            "5.7.0",
            "5.6.0-beta1",
            "5.5.0-rc1",
            "5.5.0-beta1",
            "5.5.0-alpha1",
            "5.5.0",
            "5.4.0-beta1",
            "5.0.4",
            "5.0.3",
            "5.0.2",
            "5.0.1",
            "5.0.0",
            "3.3.2",
            "3.3.1",
            "3.3.0",
            "3.2.3",
            "3.2.2",
            "3.2.1",
            "3.2.0",
            "3.1.2",
            "3.1.1",
            "3.1.0",
            "3.0.6",
            "3.0.5",
            "3.0.4",
            "3.0.3",
            "3.0.2",
            "3.0.1-rc1",
            "3.0.1",
            "2.1.0",
            "2.0.0",
            "1.3.1",
            "1.3.0",
            "1.2.0",
            "1.1.1",
            "1.1.0",
            "1.0.0"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-54718.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:33.579834590Z",
      "provider": "osv",
      "references": [
        "https://github.com/silverstripe/silverstripe-advancedworkflow/releases/tag/6.4.5",
        "https://github.com/silverstripe/silverstripe-advancedworkflow/releases/tag/7.1.3",
        "https://github.com/silverstripe/silverstripe-advancedworkflow/releases/tag/7.2.1",
        "https://www.silverstripe.org/download/security-releases/cve-2026-54718",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/54xxx/CVE-2026-54718.json",
        "https://github.com/silverstripe/silverstripe-advancedworkflow/security/advisories/GHSA-39mm-rwm3-29jp",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-54718",
        "https://github.com/silverstripe/silverstripe-advancedworkflow/commit/28d0b536491e5c68b1c445579bdd1ddc8beaf8bb",
        "https://github.com/silverstripe/silverstripe-advancedworkflow/commit/f170766af992ed2ed3e5f21d127d0d0d3129678b",
        "https://github.com/silverstripe/silverstripe-advancedworkflow/pull/629",
        "https://github.com/silverstripe/silverstripe-advancedworkflow/pull/630"
      ],
      "provider_metadata": {
        "cwe_ids": [
          "CWE-1336"
        ],
        "cna_assigner": "GitHub_M",
        "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/54xxx/CVE-2026-54718.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-54718",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 500482,
  "published_at": "2026-08-27T17:19:51.691+00:00"
}