CVE-2026-125749

Description

TaxHacker through 0.8.5 contains an insecure direct object reference vulnerability in app/(app)/settings/actions.ts that allows authenticated users to modify other users' data by supplying an arbitrary userId. Attackers can invoke Server Actions like deleteCategoryAction or editFieldAction with a victim's UUID to delete categories, clear transaction assignments, or alter LLM prompts.

References

• https://github.com/vas3k/TaxHacker/blob/v0.8.5/app/(app)/settings/actions.ts#L117-L306
• https://github.com/vas3k/TaxHacker/commit/d84a912f3a06b141cc275bb07115a204e7f10128
• https://github.com/vas3k/TaxHacker/issues/204
• https://hackmd.io/@hieund/taxhacker-settings-crud-actions-cross-user-authz
• https://www.vulncheck.com/advisories/taxhacker-through-0.8.5-idor-via-settings-server-actions-userid