What is the CVSS score of CVE-2026-33400?

CVE-2026-33400 has a CVSS 3.1 base score of 5.4 (Medium). CVSS vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N. EPSS exploitation probability: 0.0%.

Which versions of Wallos are affected by CVE-2026-33400?

Organizations using Wallos should be aware of moderate risk from CVE-2026-33400, a cross-site scripting vulnerability rated CVSS 5.4.. A patch is available.

How to fix or mitigate CVE-2026-33400?

Within 30 days: Identify affected systems and apply vendor patches as part of regular patch cycle. Verify Content-Security-Policy and output encoding.

Wallos CVE-2026-33400

EUVD-2026-14946 MEDIUM

Cross-site Scripting (XSS) (CWE-79)

2026-03-24 GitHub_M

XSS Wallos

5.4

CVSS 3.1 · GitHub Advisory

Severity by source

GitHub Advisory PRIMARY

5.4 MEDIUM

AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N

Primary rating from GitHub Advisory · only source for this CVE.

CVSS VectorGitHub Advisory

CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N

Attack Vector

Network

Attack Complexity

Low

Privileges Required

Low

User Interaction

Required

Scope

Changed

Confidentiality

Low

Integrity

Low

Availability

None

Lifecycle Timeline

Patch available

Apr 16, 2026 - 05:29 EUVD

4.7.0

EUVD ID Assigned

Mar 24, 2026 - 18:15 euvd

EUVD-2026-14946

Analysis Generated

Mar 24, 2026 - 18:15 vuln.today

CVE Published

Mar 24, 2026 - 17:45 nvd

MEDIUM 5.4

DescriptionGitHub Advisory

Wallos is an open-source, self-hostable personal subscription tracker. Prior to version 4.7.0, a stored cross-site scripting (XSS) vulnerability in the payment method rename endpoint allows any authenticated user to inject arbitrary JavaScript that executes when any user visits the Settings, Subscriptions, or Statistics pages. Combined with the wallos_login authentication cookie lacking the HttpOnly flag, this enables full session hijacking. This issue has been patched in version 4.7.0.

AnalysisAI

A stored cross-site scripting (XSS) vulnerability exists in Wallos versions prior to 4.7.0 within the payment method rename endpoint that allows authenticated users to inject arbitrary JavaScript code. When any user visits the Settings, Subscriptions, or Statistics pages, the injected malicious script executes in their browser context. This vulnerability is compounded by the wallos_login authentication cookie lacking the HttpOnly flag, enabling attackers to steal session tokens and achieve full account compromise through session hijacking.

Technical ContextAI

Wallos (CPE: cpe:2.3:a:ellite:wallos:*:*:*:*:*:*:*:*) is an open-source, self-hostable personal subscription tracker application. The vulnerability is classified as CWE-79 (Improper Neutralization of Input During Web Page Generation, commonly known as Cross-site Scripting). The root cause stems from insufficient input validation and output encoding in the payment method rename endpoint, allowing user-supplied data to be stored in the application database and later rendered without proper sanitization. The secondary issue—missing HttpOnly flag on the wallos_login authentication cookie—violates HTTP cookie security best practices and allows JavaScript code running in the same origin to access sensitive session tokens, thereby enabling cross-site request forgery and session hijacking attacks.

RemediationAI

Immediately upgrade Wallos to version 4.7.0 or later to receive the XSS fix and any related security hardening. Visit the GitHub Security Advisory at https://github.com/ellite/Wallos/security/advisories/GHSA-p6v5-227f-f3fv for detailed patch instructions. As interim mitigations prior to upgrade, implement Content Security Policy (CSP) headers with strict script-src directives to block inline script execution, enforce HTTPS-only communication, and add the HttpOnly and Secure flags to all session cookies via application configuration or reverse proxy headers. Additionally, audit all payment method entries created by untrusted users and consider restricting payment method rename functionality to administrators only until patching is complete.