Quick answer
Direct answer
Risk scores
| CVSS metric | What it means |
|---|---|
| Attack vector (AV:N) | Network: reachable remotely |
| Attack complexity (AC:L) | Low complexity |
| Privileges required (PR:H) | High privileges required |
| User interaction (UI:N) | No user interaction |
| Scope (S:C) | Scope changed: impact spreads beyond the component |
| Confidentiality (C:H) | High confidentiality impact |
| Integrity (I:L) | Low integrity impact |
| Availability (A:N) | No availability impact |
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:L/A:N
About Invoiceshelf
CVE-2026-34366 affects Invoiceshelf, a product from Invoiceshelf. Before acting, confirm where Invoiceshelf runs in your estate, who owns it and whether it is reachable from the internet, because exposure decides real risk more than the score alone.
What the flaw is
In plain terms: InvoiceShelf is an open-source web & mobile app that helps track expenses, payments and create professional invoices and estimates. Prior to version 2.2.0, a Server-Side Request Forgery (SSRF) vulnerability exists in the Payment receipt PDF generation module. User-supplied HTML in the payment Notes field is passed unsanitised to the Dompdf rendering library, which will fetch any remote resources referenced in the markup. The vulnerability is exploitable directly via the PDF receipt endpoint, regardless of whether automated email attachments are enabled. This issue has been patched in version 2.2.0.
The weakness class is Server Side Request Forgery. The server can be made to send requests to internal or arbitrary systems.
Based on its CVSS vector, the flaw can be reached over the network, needs some level of access, and needs no user interaction. Apply the vendor fix and confirm exposure on internet facing and business critical assets first.
Affected versions and timeline
| Field | Detail |
|---|---|
| Product | Invoiceshelf |
| Affected versions | Invoiceshelf before 2.2.0 |
| Published | Mar 31, 2026 |
| Last modified | Jul 24, 2026 |
| Added to CISA KEV | Not listed |
| Assigning CNA | security-advisories@github.com |
How to detect it
- Inventory every instance of Invoiceshelf and record the running version against the affected range above.
- Check external attack surface scans for internet facing instances of the component.
- Review logs on affected systems for unusual requests, errors or new processes around the vulnerable function.
- Confirm with an authenticated vulnerability scan once your scanner has a check for this CVE.
How to fix it
- Apply the fixed version of Invoiceshelf named in the vendor advisory.
- If patching must wait, restrict network access to the affected service and put it behind authentication or a web application firewall rule.
- Rescan after the change to prove the exposure is gone, then close the ticket.
CTEM action plan
| CTEM stage | What to do for this CVE |
|---|---|
| Scope | Add every business service that depends on Invoiceshelf to the current CTEM cycle. |
| Discover | Find all instances, including shadow and cloud deployments, and record versions and exposure. |
| Prioritize | Rank using EPSS and CVSS together with asset exposure and business impact. |
| Validate | Confirm the flaw is reachable and exploitable in your environment and that compensating controls work. |
| Mobilize | Assign the fix to the asset owner with a due date matched to the priority, then verify closure. |
CWE References
- CWE-918: Server Side Request Forgery More CVEs with this weakness
Technical References
Frequently asked questions
Related CVEs
InvoiceShelf is an open-source web & mobile app that helps track expenses, payments and create professional invoices and estimates. Prior to version 2.2.0, a Server-Side Request Forgery (SSRF) vulnerability exists in the Invoice PDF generation module. User-supplied HTML in the invoice Notes field is passed unsanitised to the Dompdf rendering library, which will fetch any remote resources referenced in the markup. This can be triggered via the PDF preview and email delivery endpoints. This issue has been patched in version 2.2.0.
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