GHSA-8wvg-r2j4-3737: Vikunja Assignee Email Addresses Disclosed To Vulnerability

MODERATE
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CWE-200
Published
Advisory Summary

GHSA-8wvg-r2j4-3737 is a MODERATE assignee email addresses disclosed to vulnerability (CWE-200: Exposure of Sensitive Information to an Unauthorized Actor) affecting Vikunja libraries in the Go ecosystem. The issue involves assignee email addresses disclosed to read-only project members via the task assignees endpoint. Remediation is available by upgrading affected packages to version 2.6.0.

GHSA-8wvg-r2j4-3737 at a Glance

CVE Identifier N/A
GHSA Identifier GHSA-8wvg-r2j4-3737
Severity MODERATE
CVSS v3.1 Base Score N/A
CWE Classification CWE-200: Exposure of Sensitive Information to an Unauthorized Actor
Affected Product Vikunja
Package Ecosystem Go
Published Date
Last Updated

How to Fix GHSA-8wvg-r2j4-3737

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

code.vikunja.io/api fixed: 2.6.0 
Upgrade code.vikunja.io/api to 2.6.0
Verify Direct and Transitive Dependencies

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

inspect dependencies for code.vikunja.io/api

How to Check if You Are Affected

To determine whether your application is affected by GHSA-8wvg-r2j4-3737, inspect your project dependencies for Vikunja:

inspect dependencies for code.vikunja.io/api

Analyze the terminal output to locate any version of Vikunja in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 2.6.0), your application is affected.

Note: Verify declared build manifests and deployed runtime container environments.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-200: Exposure of Sensitive Information to an Unauthorized Actor, where the product exposes sensitive information to an actor that is not explicitly authorized to have access to that information. In Vikunja, 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

### Summary `TaskAssginee.ReadAll` returns assignee user objects without blanking the `Email` field, disclosing assignee email addresses to any read-only project member. Every sibling path that returns user objects obfuscates the email; this one does not. ### Details `pkg/models/task_assignees.go` (~lines 306-344) does `Select("users.*")` and returns the result directly. `User.Email` is `json:"email,omitempty"`, so a non-empty value always serializes. The endpoint gates on `task.CanRead`, so a read-only member passes. Sibling paths blank the field: `pkg/models/tasks.go:530`, `pkg/models/project_users.go:216`, `pkg/models/teams.go:177`, `pkg/models/label_task.go:312`, `pkg/models/task_attachment.go:511`. The omission here reads as an oversight, not a decision. The same file's `getRawTaskAssigneesForTasks` (~line 56) also selects `users.*` but is safe because its only caller (`addAssigneesToTasks`) blanks the email afterwards. ### PoC (verified at runtime against v2.5.0, v1 and v2) ``` GET /api/v1/tasks/{id}/assignees (reader with permission:0) -> [{"id":37,"username":"...","email":"assignee+SECRET@example.test", ...}] ``` Same leak on `GET /api/v2/tasks/{id}/assignees` (routes through the identical model method). Contrast: `GET /api/v1/projects/{id}/projectusers` and the project task-embed both return the same users with no email. ### Impact Disclosure of assignees' email addresses to users who should only see usernames. Read-only. ### Fix Blank `Email` on each returned user in `TaskAssginee.ReadAll` before returning, matching the sibling paths. Covers v1 and v2 at once.

GHSA-8wvg-r2j4-3737 Affected Vikunja Versions

1 component(s)
Fixed Versions:
2.6.0
Product / Package Ecosystem Affected Versions Fixed Version
code.vikunja.io/api
golang/code.vikunja.io/api
Go
< 2.6.0
2.6.0

References

GitHub Advisory / Wiki ADVISORY
https://github.com/go-vikunja/vikunja/security/advisories/GHSA-8wvg-r2j4-3737
Vikunja Source Repository REPOSITORY
https://github.com/go-vikunja/vikunja/pull/3688
Vikunja Source Repository REPOSITORY
https://github.com/go-vikunja/vikunja
Vikunja Release RELEASE
https://github.com/go-vikunja/vikunja/releases/tag/v2.6.0

Frequently Asked Questions

What is GHSA-8wvg-r2j4-3737?
GHSA-8wvg-r2j4-3737 is a security vulnerability in Vikunja involving Assignee email addresses disclosed to read-only project members via the task assignees endpoint under CWE-200: Exposure of Sensitive Information to an Unauthorized Actor.
Which Vikunja versions are affected?
Affected versions include releases prior to 2.6.0 across affected packages: code.vikunja.io/api.
What version fixes GHSA-8wvg-r2j4-3737?
Upgrading to 2.6.0 (or the latest patched release for your respective branch) resolves the vulnerability.
Is code.vikunja.io/api affected?
Yes, code.vikunja.io/api is affected in releases prior to 2.6.0. Upgrade your dependency to 2.6.0 or later.
What CWE is associated with GHSA-8wvg-r2j4-3737?
GHSA-8wvg-r2j4-3737 is classified under CWE-200: Exposure of Sensitive Information to an Unauthorized Actor (The product exposes sensitive information to an actor that is not explicitly authorized to have access to that information.).
How can I check Go dependencies for GHSA-8wvg-r2j4-3737?
Run the dependency tree command: 'inspect dependencies for code.vikunja.io/api'. 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-8wvg-r2j4-3737",
  "modified" : "2026-10-09T20:54:49Z",
  "published" : "2026-10-09T20:54:49Z",
  "aliases" : [ ],
  "summary" : "Vikunja: Assignee email addresses disclosed to read-only project members via the task assignees endpoint",
  "details" : "### Summary\n`TaskAssginee.ReadAll` returns assignee user objects without blanking the `Email` field, disclosing assignee email addresses to any read-only project member. Every sibling path that returns user objects obfuscates the email; this one does not.\n\n### Details\n`pkg/models/task_assignees.go` (~lines 306-344) does `Select(\"users.*\")` and returns the result directly. `User.Email` is `json:\"email,omitempty\"`, so a non-empty value always serializes. The endpoint gates on `task.CanRead`, so a read-only member passes. Sibling paths blank the field: `pkg/models/tasks.go:530`, `pkg/models/project_users.go:216`, `pkg/models/teams.go:177`, `pkg/models/label_task.go:312`, `pkg/models/task_attachment.go:511`. The omission here reads as an oversight, not a decision.\n\nThe same file's `getRawTaskAssigneesForTasks` (~line 56) also selects `users.*` but is safe because its only caller (`addAssigneesToTasks`) blanks the email afterwards.\n\n### PoC (verified at runtime against v2.5.0, v1 and v2)\n```\nGET /api/v1/tasks/{id}/assignees   (reader with permission:0)\n-> [{\"id\":37,\"username\":\"...\",\"email\":\"assignee+SECRET@example.test\", ...}]\n```\nSame leak on `GET /api/v2/tasks/{id}/assignees` (routes through the identical model method). Contrast: `GET /api/v1/projects/{id}/projectusers` and the project task-embed both return the same users with no email.\n\n### Impact\nDisclosure of assignees' email addresses to users who should only see usernames. Read-only.\n\n### Fix\nBlank `Email` on each returned user in `TaskAssginee.ReadAll` before returning, matching the sibling paths. Covers v1 and v2 at once.",
  "severity" : [ {
    "type" : "CVSS_V4",
    "score" : "CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "Go",
      "name" : "code.vikunja.io/api"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "2.6.0"
      } ]
    } ],
    "database_specific" : {
      "last_known_affected_version_range" : "<= 2.5.0"
    }
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/go-vikunja/vikunja/security/advisories/GHSA-8wvg-r2j4-3737"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/go-vikunja/vikunja/pull/3688"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/go-vikunja/vikunja"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/go-vikunja/vikunja/releases/tag/v2.6.0"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-200" ],
    "severity" : "MODERATE",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-10-09T20:54:49Z",
    "nvd_published_at" : null
  }
}