Nextcloud Whiteboard up to 0.x server-side request forgery

CVSS Meta Temp Score
CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.
Current Exploit Price (≈)
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CTI Interest Score
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4.9$0-$5k1.00

Summaryinfo

A vulnerability was found in Nextcloud Whiteboard up to 0.x. It has been declared as critical. This affects an unknown part. The manipulation results in server-side request forgery. This vulnerability is known as CVE-2026-87897. It is possible to launch the attack remotely. No exploit is available. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as critical, was found in Nextcloud Whiteboard up to 0.x. Affected is some unknown processing. The manipulation with an unknown input leads to a server-side request forgery vulnerability. CWE is classifying the issue as CWE-918. The web server receives a URL or similar request from an upstream component and retrieves the contents of this URL, but it does not sufficiently ensure that the request is being sent to the expected destination. This is going to have an impact on confidentiality, integrity, and availability. CVE summarizes:

A SSRF vulnerability found that enables access to internal Chrome Devtools Protocol APIs that can leak the JWT authentication token for another user. A low privileged attacker could continually exploit this vulnerability to leak the JWT authentication token for another user when they start a recording, which then enables the attacker read/write access to the victim's Whiteboard.

The advisory is shared for download at hackerone.com. This vulnerability is traded as CVE-2026-87897 since 09/09/2026. The exploitability is told to be easy. It is possible to launch the attack remotely. Successful exploitation requires user interaction by the victim. There are neither technical details nor an exploit publicly available.

Upgrading to version 1.0.0 eliminates this vulnerability.

VulDB is the best source for vulnerability data and more expert information about this specific topic.

Productinfo

Type

Vendor

Name

Version

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.1
VulDB Meta Temp Score: 4.9

VulDB Base Score: 5.5
VulDB Temp Score: 5.3
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 4.6
CNA Vector (hackerone): 🔒

CVSSv2info

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

Exploitinginfo

Class: Server-side request forgery
CWE: CWE-918
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: Whiteboard 1.0.0

Timelineinfo

09/09/2026 CVE reserved
10/27/2026 +48 days Advisory disclosed
10/27/2026 +0 days VulDB entry created
10/27/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: hackerone.com
Status: Confirmed

CVE: CVE-2026-87897 (🔒)
GCVE (CVE): GCVE-0-2026-87897
GCVE (VulDB): GCVE-100-427440

Entryinfo

Created: 10/27/2026 17:37
Changes: 10/27/2026 17:37 (63)
Complete: 🔍
Cache ID: 216::103

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