CVE-2026-33742 | Invoice Ninja has Stored XSS via Markdown HTML Injection in Product Notes

Exp

Invoice Ninja is a source-available invoice, quote, project and time-tracking app built with Laravel. Product notes fields in Invoice Ninja v5.13.0 allow raw HTML via Markdown rendering, enabling stored XSS. The Markdown parser output was not sanitized with `purify::clean()` before being included in invoice templates. This is fixed in v5.13.4 by the vendor by adding `purify::clean()` to sanitize Markdown output.

Published: 2026-03-26 Last update: 2026-03-30 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2026-33742 is rated Exploit Available (50/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.03%). Core evidence: 1 public exploit reference(s) are indexed (Exploit-DB). Mandatory action: Public exploits are available—assess exposure, apply mitigations, and prioritize patching.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Public exploit references (Exploit-DB) for CVE-2026-33742

EDB-ID Source Kind Published Link
nvd_ref exploit_tag Exploit-DB ↗

Exploit prediction scoring system (EPSS) score for CVE-2026-33742

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-03-27 0.03%

Full EPSS history (1 record total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-33742

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
5.4 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:N)
Service keeps running; no real outage angle.
2.3 2.7 [email protected]

Weakness enumeration for CVE-2026-33742

Affected software / configurations for CVE-2026-33742

Vendor Product Version Raw CPE
invoiceninja invoice_ninja < 5.13.4 cpe:2.3:a:invoiceninja:invoice_ninja:*:*:*:*:*:*:*:*

References for CVE-2026-33742

cvelogic Threat Intelligence