CVE-2026-82727 ash-project CVE debrief

Who should care

Developers and administrators using ash_phoenix versions between 1.2.17 and 2.3.25 should review and remediate this vulnerability to prevent sensitive information leakage. They should focus on AshPhoenix.Form.Auto union sub-form handling and parameter filtering. Additionally, operators, platform administrators, vulnerability management teams, and security teams should be aware of the potential impact and take necessary actions to protect their systems and data. Compensating controls, such as monitoring and redacting sensitive information in logs and error reports, should be implemented while remediation is scheduled and verified. Asset inventory and rollback/change windows should also be considered to minimize exposure. Source tracking and exposure review are crucial in this process. Security teams should verify vendor remediation by upgrading to ash_phoenix version 2.3.25 or later. They should also check relevant monitoring, detection, and logs for exposed assets that need extra review and track exceptions, retest remediated assets, and close the item only after evidence is documented. The CVE record was published on 2026-08-31T04:17:29.560Z and has not been modified since then. The CVSS score is 2.3, and the severity is LOW. The vulnerability is related to the ash-project and ash_phoenix. The NVD and CVE Program records provide additional information on this issue. To address this vulnerability, it is essential to review AshPhoenix.Form.Auto union sub-form handling and parameter filtering to prevent sensitive information leakage. This can be achieved by reporting only the offending _union_type and valid type names, dropping the param and constraints dumps. Upgrading to ash_phoenix version 2.3.25 or later will remediate the vulnerability. Implementing compensating controls, such as monitoring and redacting sensitive information in logs and error reports, can help mitigate the issue while remediation is scheduled and verified. It is also crucial to verify vendor remediation and track exceptions, retest remediated assets, and close the item only after evidence is documented. The AshPhoenix.Form.Auto module in ash_phoenix is vulnerable to sensitive information. A

Technical summary

The AshPhoenix.Form.Auto module in ash_phoenix is vulnerable to sensitive information leakage. When a union sub-form is built and the submitted _union_type does not match a configured type, an exception message is raised containing the entire raw submitted param map. This allows attackers to leak secrets submitted alongside a union form field into logs, crash reports, and the dev error page. The issue affects ash_phoenix versions from 1.2.17 before 2.3.25.

Defensive priority

Review AshPhoenix.Form.Auto union sub-form handling and parameter filtering to prevent sensitive information leakage.

Recommended defensive actions

• Review AshPhoenix.Form.Auto union sub-form handling and parameter filtering to prevent sensitive information leakage.
• Implement compensating controls to monitor and redact sensitive information in logs and error reports.
• Verify vendor remediation by upgrading to ash_phoenix version 2.3.25 or later.
• Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up.
• Review the supplied official advisory or CVE record to validate affected scope, severity, and vendor guidance.
• Plan vendor-supported updates or mitigations through normal change control where exposure is confirmed.
• Check relevant monitoring, detection, and logs for exposed assets that need extra review.

Evidence notes

The CVE-2026-82727 issue arises from AshPhoenix.Form.Auto's handling of union sub-forms. When the submitted _union_type does not match a configured type, the library raises an exception message containing the full untrusted param map. This allows attackers to leak secrets submitted alongside a union form field into logs, crash reports, and the dev error page. The fix reports only the offending _union_type and valid type names, omitting the param and constraints dumps.

Sources and 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.