PatchSiren

PatchSiren cyber security CVE debrief

CVE-2026-47266 verbb CVE debrief

CVE-2026-47266 is a HIGH severity (CVSS 8.7) authorization bypass in the Formie plugin for Craft CMS. Unauthenticated attackers can modify existing form submissions by submitting a known or guessed submission ID to the `formie/submissions/save-submission` endpoint. The vulnerability affects versions prior to 2.2.21 (v2.x branch) and 3.1.26 (v3.x branch). The issue was disclosed on 2026-05-29 with fixes released the same day. No known exploitation in ransomware campaigns has been reported.

Vendor
verbb
Product
formie
CVSS
HIGH 8.7
CISA KEV
Not listed in stored evidence
Original CVE published
2026-05-29
Original CVE updated
2026-07-22
Advisory published
2026-05-29
Advisory updated
2026-07-22

Who should care

Organizations running Craft CMS with the Formie plugin for form management, particularly those handling sensitive submission data or compliance-regulated information. Security teams should prioritize patching due to the unauthenticated attack vector and data integrity impact.

Technical summary

The Formie plugin's `formie/submissions/save-submission` endpoint fails to properly validate ownership or session state when processing submission updates. By providing a valid submission ID, unauthenticated attackers can overwrite existing submission data. The vulnerability stems from missing authorization checks that would verify the submitter's right to modify the targeted submission.

Defensive priority

HIGH

Recommended defensive actions

  • Upgrade Formie to version 2.2.21 or later (v2.x) or 3.1.26 or later (v3.x)
  • Review form submission logs for unauthorized modifications to existing submissions
  • Implement additional access controls or rate limiting on form submission endpoints if immediate patching is not feasible
  • Audit existing submissions for data integrity, particularly those with sequential or predictable IDs

Evidence notes

The vulnerability description and fix versions are sourced from the official CVE record and GitHub Security Advisory. The CVSS 4.0 vector (AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N) confirms network-accessible, unauthenticated attack with high integrity impact. CWE-639 (Authorization Bypass Through User-Controlled Key) is the assigned weakness.

Sources and references

Verified primary and authoritative sources

  • CVE-2026-47266 CVE Program record

    Publisher, destination, and source semantics verified

    URL: https://www.cve.org/CVERecord?id=CVE-2026-47266

    CVE Program - Official CVE Program record with source-provided CVE metadata.

  • CVE-2026-47266 NVD vulnerability detail

    Publisher, destination, and source semantics verified

    URL: https://nvd.nist.gov/vuln/detail/CVE-2026-47266

    NIST National Vulnerability Database - Official NIST NVD detail page and source-specific vulnerability assessment.

Supplemental references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.