Is there a public exploit for CVE-2026-55561?

No public exploit for CVE-2026-55561 was found in Exploit-DB, Metasploit, Nuclei templates or public proof-of-concept repositories. That is an absence of evidence rather than proof that none exists.

How severe is CVE-2026-55561?

CVE-2026-55561 scores CVSS 5.3 (v4.0), rated medium. EPSS puts the chance of exploitation in the next 30 days at 0.28%.

What does CVE-2026-55561 affect?

CVE-2026-55561 affects InvoicePlane InvoicePlane.

5.3 Medium

InvoicePlane is a self-hosted open source application for managing invoices, clients, and payments.

CVE-2026-55561

InvoicePlane is a self-hosted open source application for managing invoices, clients, and payments. Prior to 1.7.2-beta-1, guest users can approve or reject quotes belonging to any client, not just their assigned clients. The approve() and reject() methods in the Guest Quotes controller, application/modules/guest/controllers/Quotes.php, call approvequotebyid($quoteid) and rejectquotebyid($quoteid) directly without the wherein('ipquotes.clientid', $this->userclients) scoping that sibling methods use. A guest user assigned to one client can change another client's quote status by supplying sequential integer quoteid values, and emailquotestatus() also sends notification emails. Additionally, generatepdf() calls markviewed($quoteid) before checking the client scope, allowing a guest user to mark another client's quote as viewed. These issues are fixed in version 1.7.2-beta-1 and the subsequent stable version 1.7.2.

Assessment

CVSS: 5.3 (v4.0)
Severity: Medium
EPSS: 0.28% chance of exploitation in the next 30 days
Known exploited: Not listed in CISA KEV
Exploit availability: Nothing found in Exploit-DB, Metasploit, Nuclei or public PoC repositories
Published: 28 October 2026
Last updated: 3 November 2026
Affected: InvoicePlane · InvoicePlane
Assigner: GitHub_M

CVSS vectorCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N

At the source

EUVD (ENISA)

References

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