CVE-2026-55610
InvoiceShelf is an open-source web & mobile app that helps track expenses, payments and create professional invoices and estimates. Prior to version 2.4.1, in InvoiceShelf's multi-company installations, any user who is an Owner of one company can read and overwrite any user account in any other company on the same installation. `GET/PUT /api/v1/users/{user}` resolves the target `User` by global primary key, and `UserPolicy` checks only that the requester owns their own header-company — it never verifies that the target user belongs to that company. This allows cross-tenant disclosure of user data and full account takeover (email/password overwrite + company re-assignment). Version 2.4.1 fixes the issue.
What this means for your business
- An attacker can use it remotely, over a network, with an administrator login, and without anyone at your company clicking anything.
What to do
- 1Ask your IT team or provider whether any of your systems use the affected product.
- 2If you do, follow the vendor's guidance. No patch reference has been published yet.
Not sure if your company is exposed?
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Scoring
- CVSS
- 8.7 (v3.1)
- Vector
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:N- Weakness
- CWE-639
- Assigned by
- security-advisories@github.com
Dates
- Published
- 2026-09-23
- Last modified
- 2026-09-23
- Sources
- NVD