VulnerabilityPublished 24 Mar 2026

CVE-2026-33676: vikunja · Incorrect Authorization

Affects vikunjaSource CVE Database V5

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Not known to be exploited · CVSS 6.5 Medium : upgrade to 2.2.1 when convenient.

Data as of 30 Oct 2026, 06:59 UTC

CVSS 3.1 base score

6.5Medium

How severe the flaw is on the 0–10 CVSS scale.

EPSS: 0.3% chance of exploitation in 30 days – higher than 30% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch: Available – fixed in 2.2.1

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

Attack Vector: Network
Attack Complexity: Low
Privileges Required: Low
User Interaction: None
Scope: Unchanged
Confidentiality: High
Integrity: None
Availability: None

Bold values are the worst case: easiest to exploit or largest impact.

Attack Vector: Network: The vulnerable component is bound to the network stack and the set of possible attackers extends beyond the other options listed, up to and including the entire Internet. Such a vulnerability is often termed 'remotely exploitable' and can be thought of as an attack being exploitable at the protocol level one or more network hops away (e.g., across one or more routers).
Attack Complexity: Low: Specialized access conditions or extenuating circumstances do not exist. An attacker can expect repeatable success against the vulnerable component.
Privileges Required: Low: The attacker is authorized with (i.e., requires) privileges that provide basic user capabilities that could normally affect only settings and files owned by a user. Alternatively, an attacker with Low privileges may have the ability to cause an impact only to non-sensitive resources.
User Interaction: None: The vulnerable system can be exploited without any interaction from any user.
Scope: Unchanged: An exploited vulnerability can only affect resources managed by the same security authority. In this case, the vulnerable component and the impacted component are either the same, or both are managed by the same security authority.
Confidentiality: High: There is total loss of confidentiality, resulting in all resources within the impacted component being divulged to the attacker. Alternatively, access to only some restricted information is obtained, but the disclosed information presents a direct, serious impact.
Integrity: None: There is no loss of integrity within the impacted component.
Availability: None: There is no impact to availability within the impacted component.

Definitions: FIRST CVSS v3.1 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 24 Mar 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 29 Oct 2026.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponized: A Metasploit exploit module or Exploit-DB entry exists (Metasploit scanner modules do not count), or CISA SSVC or the CVSS exploit maturity reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

What to do

Upgrade vikunja and github.com/go-vikunja/vikunja to 2.2.1.

Affected software

Product	Affected	Fixed in
go-vikunjavikunja	Affected <2.2.1	Fixed in 2.2.1
Gogithub.com/go-vikunja/vikunja`pkg:golang/github.com/go-vikunja/vikunja`Other threats	Affected <2.2.1	Fixed in 2.2.1

Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.

AI-suggested

Organizations should upgrade all Vikunja instances to version 2.2.1 or later, where the authorization checks for related tasks have been properly implemented. Until upgrading is possible, administrators can mitigate risk by restricting task read permissions to trusted users only and minimizing cross-project task relations that could expose sensitive data. Reviewing and tightening project and task access controls can reduce the attack surface. Monitoring API access logs for unusual patterns of task retrieval may help detect attempts to exploit this vulnerability. Additionally, organizations should educate users about the sensitivity of task data and enforce the principle of least privilege for task access. If custom integrations or API clients are used, they should be reviewed to ensure they do not inadvertently expose related task data. Finally, applying network-level protections such as VPNs or IP whitelisting can limit access to the Vikunja API to authorized personnel only.

Description

CVE-2026-33676 is an authorization vulnerability in the open-source task management platform Vikunja prior to version 2.2.1. The flaw allows authenticated users with read access to a task to receive full details of related tasks in projects they do not have permission to access. This occurs because the API populates the 'related_tasks' field with full task objects without verifying read permissions on those related tasks' projects. The exposed information includes sensitive task details such as title, description, due dates, priority, percent completion, and project IDs. The vulnerability has a CVSS score of 6.5 (medium severity) and does not impact task integrity or availability, only confidentiality. Version 2.2.

Impact

The primary impact of CVE-2026-33676 is unauthorized disclosure of sensitive task information across project boundaries within Vikunja deployments. Organizations using affected versions risk leaking confidential project details such as task descriptions, deadlines, priorities, and progress metrics to unauthorized users who have limited access rights. This can lead to information exposure that may compromise project confidentiality, competitive advantage, or privacy. While the vulnerability does not allow modification or deletion of data, the unauthorized visibility of sensitive task information can facilitate social engineering, insider threats, or competitive intelligence gathering. Since Vikunja is often used for internal task and project management, the exposure of cross-project task details could undermine trust in the platform and violate data protection policies. The vulnerability affects all organizations running Vikunja versions prior to 2.2.1, especially those with multi-project environments and users with varying access levels. No known exploits are reported in the wild yet, but the ease of exploitation by any authenticated user with read access to at least one task makes timely remediation important.

CWE-863Incorrect Authorization (opens in a new tab)
Class weaknessLikelihood of exploit: HighCWE Top 25 (2025): #17OWASP Top 10 A01:2025: Broken Access Control (opens in a new tab)
The product performs an authorization check when an actor attempts to access a resource or perform an action, but it does not correctly perform the check.
Architecture and Design
Divide the product into anonymous, normal, privileged, and administrative areas. Reduce the attack surface by carefully mapping roles with data and functionality. Use role-based access control (RBAC) to enforce the roles at the appropriate boundaries.
Architecture and Design
Ensure that access control checks are performed related to the business logic. These checks may be different than the access control checks that are applied to more generic resources such as files, connections, processes, memory, and database records.
Architecture and Design · Libraries or Frameworks
Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid.
OWASP Cheat Sheets
Authorization (opens in a new tab)
OWASP ASVS 4.0.3
V8.3.8 (opens in a new tab)
V13.4.2 (opens in a new tab)
V7.2.2 (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 31 Mar 2026, 20:36 UTC

WeaknessesCWE-863

Technical details

References

Community reviews

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