TI-2026-26058 Aliases CVE-2026-33678 GHSA-jfmm-mjcp-8wq2

Vikunja has IDOR in Task Attachment ReadOne Allows Cross-Project File Access and Deletion

LOW 37CWE-639Published 2026-03-24 · Updated 2026-03-24

Key facts

Attack vector: Network
Privileges required: Low
User interaction: None
Attack complexity: Low
Impact type: Security bypass
Confidentiality · integrity · availability: High · High · None
Fix status: Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA and GitHub. Impact type from CWE-639.

Summary

Vikunja is an open-source self-hosted task management platform. Prior to version 2.2.1, `TaskAttachment.ReadOne()` queries attachments by ID only (`WHERE id = ?`), ignoring the task ID from the URL path. The permission check in `CanRead()` validates access to the task specified in the URL, but `ReadOne()` loads a different attachment that may belong to a task in another project. This allows any authenticated user to download or delete any attachment in the system by providing their own accessible task ID with a target attachment ID. Attachment IDs are sequential integers, making enumeration trivial. Version 2.2.1 patches the issue.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV

EPSS 0.00318 24th percentileScored 2026-11-07

Public exploit Yes 1 exploit referenceTagged by NVD

Fix Fixed vikunja (go-vikunja): 2.2.1code.vikunja.io/api (Go): 2.2.1

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation: None
Automatable: No
Technical impact: Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

Vendor	Product	Affected versions	Fixed in	Status	Source
go-vikunja	vikunja	before 2.2.1	2.2.1	Patch available	CNA
—	code.vikunja.io/api (Go)	before 2.2.1	2.2.1	Patch available	GHSA-jfmm-mjcp-8wq2

vikunja Vendorgo-vikunja Affected before 2.2.1 Fixed in 2.2.1 Patch available CNA
code.vikunja.io/api (Go) Vendor— Affected before 2.2.1 Fixed in 2.2.1 Patch available GHSA-jfmm-mjcp-8wq2

CPE configurations NVD · 1

CPE	Versions	Role	Vendor
cpe:2.3:a:vikunja:vikunja::::::::	before 2.2.1	Vulnerable	go-vikunja

cpe:2.3:a:vikunja:vikunja:*:*:*:*:*:*:*:* Versions before 2.2.1 Vulnerable ·go-vikunja

Remediation

Fix · CNA vikunja (go-vikunja) Fixed in 2.2.1
Fix · GHSA-jfmm-mjcp-8wq2 code.vikunja.io/api (Go) Fixed in 2.2.1 Advisory →

Timeline

2026-10-02 Threatist record created from CVE-2026-33678
2026-10-03 Alias added: GHSA-jfmm-mjcp-8wq2

References

Exploit 1

https://github.com/go-vikunja/vikunja/security/advisories/GHSA-jfmm-mjcp-8wq2

Advisory 1

https://nvd.nist.gov/vuln/detail/CVE-2026-33678

Other 2

TI-2026-21967 Vijkunja has Weak Password Policy Combined with Persistent Sessions After Password Change CVSS 3.1CRITICAL 9.1
TI-2026-26971 Vikunja ahs a TOTP Two-Factor Authentication Bypass via OIDC Login Path CVSS 3.1CRITICAL 9.1
TI-2026-26060 Vikunja Vulnerable to Link Share Hash Disclosure via ReadAll Endpoint Enables Permission Escalation CVSS 3.1HIGH 7.5
TI-2026-20965 Vikunja Affected by XSS Via Task Preview CVSS 4.0HIGH 8.6
TI-2026-27698 Vikunja Affected by Privilege Escalation via Project Reparenting CVSS 3.1HIGH 8.3
TI-2026-25727 Vikunja’s Improper Access Control Enables Bypass of Administrator-Imposed Account Disablement CVSS 3.1HIGH 8.1

See all 34 →

Sources

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