go-vikunja up to 2.1.x improper authorization in handler for custom url scheme

CVSS Meta Temp Score
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CTI Interest Score
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6.6$0-$5k1.11

Summaryinfo

A vulnerability classified as problematic was found in go-vikunja vikunja up to 2.1.x. Affected by this vulnerability is an unknown functionality. Such manipulation leads to improper authorization in handler for custom url scheme. This vulnerability is traded as CVE-2026-33335. The attack may be launched remotely. There is no exploit available. Upgrading the affected component is advised.

Detailsinfo

A vulnerability was found in go-vikunja vikunja up to 2.1.x and classified as problematic. Affected by this issue is an unknown function. The manipulation with an unknown input leads to a improper authorization in handler for custom url scheme vulnerability. Using CWE to declare the problem leads to CWE-939. The product uses a handler for a custom URL scheme, but it does not properly restrict which actors can invoke the handler using the scheme. Impacted is confidentiality, integrity, and availability. CVE summarizes:

Vikunja is an open-source self-hosted task management platform. Starting in version 0.21.0 and prior to version 2.2.0, the Vikunja Desktop Electron wrapper passes URLs from `window.open()` calls directly to `shell.openExternal()` without any validation or protocol allowlisting. An attacker who can place a link with `target="_blank"` (or that otherwise triggers `window.open`) in user-generated content can cause the victim's operating system to open arbitrary URI schemes, invoking local applications, opening local files, or triggering custom protocol handlers. Version 2.2.0 patches the issue.

The advisory is available at github.com. This vulnerability is handled as CVE-2026-33335 since 03/18/2026. The exploitation is known to be easy. The attack may be launched remotely. Successful exploitation requires user interaction by the victim. The technical details are unknown and an exploit is not available.

Upgrading to version 2.2.0 eliminates this vulnerability. The upgrade is hosted for download at vikunja.io.

If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Vendor

Name

Version

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 6.7
VulDB Meta Temp Score: 6.6

VulDB Base Score: 5.5
VulDB Temp Score: 5.3
VulDB Vector: 🔒
VulDB Reliability: 🔍

NVD Base Score: 8.0
NVD Vector: 🔒

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Improper authorization in handler for custom url scheme
CWE: CWE-939 / CWE-285 / CWE-266
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: vikunja 2.2.0

Timelineinfo

03/18/2026 CVE reserved
03/24/2026 +6 days Advisory disclosed
03/24/2026 +0 days VulDB entry created
03/28/2026 +4 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: GHSA-6q44-85gc-cjvf
Status: Confirmed

CVE: CVE-2026-33335 (🔒)
GCVE (CVE): GCVE-0-2026-33335
GCVE (VulDB): GCVE-100-352814

Entryinfo

Created: 03/24/2026 17:34
Updated: 03/28/2026 22:32
Changes: 03/24/2026 17:34 (67), 03/28/2026 22:32 (12)
Complete: 🔍
Cache ID: 216:71D:103

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