CVE-2026-91983Public exploitNetwork attack vectorHinoki check available

Restricted data disclosure via unchecked task expansions

Published Sep 15, 2026 · Updated Sep 15, 2026

Incorrect authorization in Vikunja 1.0.0 through 2.5.0 allows remote authenticated users to read restricted task data via expansions. models.CanDoAPIRoute checks only the request method and route path, while task handlers honor the expand query parameter without checking the token scopes for comments, reactions, or time entries. A tasks-read API token is sufficient; disclosure remains limited to data visible to the token owner and does not permit modification.

CVSS severityUnavailable
Unscored
EPSS probability0.27%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
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Summary

What happened

Incorrect authorization in Vikunja 1.0.0 through 2.5.0 allows remote authenticated users to read restricted task data via expansions. models.CanDoAPIRoute checks only the request method and route path, while task handlers honor the expand query parameter without checking the token scopes for comments, reactions, or time entries. A tasks-read API token is sufficient; disclosure remains limited to data visible to the token owner and does not permit modification.

The record

CVE
CVE-2026-91983
Published
Sep 15, 2026
Updated
Sep 15, 2026
Vendor
Vikunja
Product
Vikunja
Classifications
CWE-863, T1213
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Sep 15, 2026CVE publishedPublication date reported by the CVE source.
  2. Sep 15, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=1.0.0 <2.6.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Vikunja · Vikunjaversion=1.0.0 <2.6.0

Published CVSS scores

No CVSS assessment is available in this record.

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-863Incorrect Authorization
T1213Data from Information Repositories

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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