Cloudreve up to 4.16.x WOPI ViewerSessionValidation improper authentication

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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6.0$0-$5k1.85

Summaryinfo

A vulnerability classified as critical has been found in Cloudreve up to 4.16.x. Affected is the function ViewerSessionValidation of the component WOPI. Performing a manipulation results in improper authentication. This vulnerability is cataloged as CVE-2026-62323. It is possible to initiate the attack remotely. There is no exploit available.

Detailsinfo

A vulnerability was found in Cloudreve up to 4.16.x. It has been classified as critical. This affects the function ViewerSessionValidation of the component WOPI. The manipulation with an unknown input leads to a improper authentication vulnerability. CWE is classifying the issue as CWE-287. When an actor claims to have a given identity, the product does not prove or insufficiently proves that the claim is correct. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

Cloudreve is a self-hosted file management and sharing system. Prior to 4.17.0, ViewerSessionValidation uses only the session-id prefix of a WOPI access token and does not enforce the requested viewer action, allowing a malicious or compromised WOPI viewer with a view session to forge the token suffix and invoke WOPI write routes for the underlying file. This issue is fixed in version 4.17.0.

It is possible to read the advisory at github.com. This vulnerability is uniquely identified as CVE-2026-62323 since 07/13/2026. The exploitability is told to be easy. It is possible to initiate the attack remotely. Technical details of the vulnerability are known, but there is no available exploit.

Upgrading to version 4.17.0 eliminates this vulnerability.

Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

Type

Name

Version

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.3
VulDB Meta Temp Score: 6.0

VulDB Base Score: 6.3
VulDB Temp Score: 6.0
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
💳💳💳💳💳💳
💳💳💳💳💳💳
💳💳💳💳💳💳
VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Improper authentication
CWE: CWE-287
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Cloudreve 4.17.0

Timelineinfo

07/13/2026 CVE reserved
07/31/2026 +18 days Advisory disclosed
07/31/2026 +0 days VulDB entry created
07/31/2026 +0 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: github.com
Status: Confirmed

CVE: CVE-2026-62323 (🔒)
GCVE (CVE): GCVE-0-2026-62323
GCVE (VulDB): GCVE-100-384999

Entryinfo

Created: 07/31/2026 06:24
Changes: 07/31/2026 06:24 (56)
Complete: 🔍
Cache ID: 216::103

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