CVE-2026-13603: Software Security Vulnerability Vulnerability

CRITICAL
Advisory Identifier: GHSA-29fq-jc8m-8rq2
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CWE-20
Published
Advisory Summary

CVE-2026-13603 is a CRITICAL security vulnerability vulnerability (CWE-20: Improper Input Validation) affecting Software libraries in the Maven ecosystem. The weakness occurs when the product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly.. Remediation is available in the latest vendor maintenance releases.

CVE-2026-13603 at a Glance

CVE Identifier CVE-2026-13603
GHSA Identifier GHSA-29fq-jc8m-8rq2
Severity CRITICAL
CVSS v3.1 Base Score N/A
CWE Classification CWE-20: Improper Input Validation
Affected Product Software
Package Ecosystem Maven
Published Date
Last Updated

How to Fix CVE-2026-13603

To remediate this vulnerability, upgrade all affected Software dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.

Verify Direct and Transitive Dependencies

Run the following command in your project directory to verify that all resolved dependencies use the patched release: 

mvn dependency:tree

How to Check if You Are Affected

To determine whether your Java application is affected by CVE-2026-13603, inspect your build dependencies using the Maven Dependency Plugin:

mvn dependency:tree

Analyze the terminal output to locate any version of Software in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than the patched release), your application is affected.

Note: The mvn dependency:tree command inspects the resolved dependency graph declared in your project's POM files; it does not perform automated security scanning or inspect runtime dynamic classpaths. Always verify runtime container classpaths and shaded JARs.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-20: Improper Input Validation, where the product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly. In Software, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.

Source Advisory Statement

The payment integration pretix-oppwa provides support for the payment providers VR Payment, Hobex, and potentially others based on Oppwa's technology. The integration of Oppwa, following their official documentation, includes a step where the user is redirected from the payment provider back to our system with a query parameter like ?resourcePath=/v1/checkouts/{checkoutId}/payment in the URL. Our system is then supposed to fetch the status of the transaction from the URL given by baseUrl + resourcePath. Our plugin pretix-oppwa did so insecurely by concatenating the parameter form the URL to the base domain of the API without further validation and, critically, without a / at the end of the baseUrl. Therefore, an attacker could inject a resourcePath argument in a way that causes pretix to call a different server instead. Since the request includes the access token (API key) of the Oppwa account, this would leak the access token, giving access to data contained in the payment provider's system. This is fixed with the release today by strictly validating the given API URL. After installing the update, we recommend asking your payment provider for a new access token and updating it in pretix.

References

NVD — CVE-2026-13603 NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-13603
pretix.eu/about/en/blog/20260... WEB
https://pretix.eu/about/en/blog/20260701-release-2026-5-3

Frequently Asked Questions

What is CVE-2026-13603?
CVE-2026-13603 is a security vulnerability in Software classified as a security vulnerability vulnerability under CWE-20: Improper Input Validation.
Which Software versions are affected?
Affected versions include releases prior to current release patches.
What version fixes CVE-2026-13603?
Upgrading to current release patches (or the latest patched release for your respective branch) resolves the vulnerability.
What CWE is associated with CVE-2026-13603?
CVE-2026-13603 is classified under CWE-20: Improper Input Validation (The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly.).
How can I check Maven dependencies for CVE-2026-13603?
Run the dependency tree command: 'mvn dependency:tree'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.
Machine-readable OSV JSON OSV v1.5 Schema
Normalized schema output
View Raw JSON 
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-29fq-jc8m-8rq2",
  "modified" : "2026-07-01T15:35:18Z",
  "published" : "2026-07-01T15:35:18Z",
  "aliases" : [ "CVE-2026-13603" ],
  "details" : "The payment integration pretix-oppwa provides support \nfor the payment providers VR Payment, Hobex, and potentially others \nbased on Oppwa's technology. The integration of Oppwa, following their \nofficial documentation, includes a step where the user is redirected \nfrom the payment provider back to our system with a query parameter like\n ?resourcePath=/v1/checkouts/{checkoutId}/payment in the URL. Our system is then supposed to fetch the status of the transaction from the URL given by baseUrl + resourcePath.\n\n\n\nOur plugin pretix-oppwa did so insecurely by \nconcatenating the parameter form the URL to the base domain of the API \nwithout further validation and, critically, without a / at the end of the baseUrl. Therefore, an attacker could inject a resourcePath argument in a way that causes pretix to call a different\n server instead. Since the request includes the access token (API key) \nof the Oppwa account, this would leak the access token, giving access to\n data contained in the payment provider's system. This is fixed with the\n release today by strictly validating the given API URL.\n\n\n\n\n\n\n\n\n\nAfter installing the update, we recommend asking your payment provider for a new access token and updating it in pretix.",
  "severity" : [ {
    "type" : "CVSS_V4",
    "score" : "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:L/SC:H/SI:H/SA:L/E:U/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X"
  } ],
  "affected" : [ ],
  "references" : [ {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-13603"
  }, {
    "type" : "WEB",
    "url" : "https://pretix.eu/about/en/blog/20260701-release-2026-5-3"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-20" ],
    "severity" : "CRITICAL",
    "github_reviewed" : false,
    "github_reviewed_at" : null,
    "nvd_published_at" : "2026-07-01T14:16:31Z"
  }
}