CVE-2026-53620Network attack vectorHinoki check available

Cross-account bookmark manipulation via unchecked folder ownership

Published Aug 31, 2026 · Updated Aug 31, 2026

Authorization bypass in GROWI 8.0.0 and earlier allows remote authenticated users to read, alter, or delete other users' bookmark data. Bookmark-folder API endpoints accept a user-controlled folder key without verifying that the referenced folder belongs to the requesting account. Any logged-in general user can rename, restructure, populate, or recursively delete another user's bookmark folders, and automated requests can apply those operations across accounts.

CVSS severity5.3
Medium
EPSS probability0.29%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
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Summary

What happened

Authorization bypass in GROWI 8.0.0 and earlier allows remote authenticated users to read, alter, or delete other users' bookmark data. Bookmark-folder API endpoints accept a user-controlled folder key without verifying that the referenced folder belongs to the requesting account. Any logged-in general user can rename, restructure, populate, or recursively delete another user's bookmark folders, and automated requests can apply those operations across accounts.

The record

CVE
CVE-2026-53620
Published
Aug 31, 2026
Updated
Aug 31, 2026
Vendor
WESEEK, Inc.
Product
GROWI
Classifications
CWE-639
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Aug 31, 2026CVE publishedPublication date reported by the CVE source.
  2. Aug 31, 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=0 <=v8.0.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

WESEEK, Inc. · GROWIversion=0 <=v8.0.0

Published CVSS scores

5.3JPCERT/CC and IPACVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N
6.3JPCERT/CC and IPACVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L

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.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-639Authorization Bypass Through User-Controlled Key

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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