BookStackApp BookStack up to 26.05.3 Drawing Upload Endpoint cross site scripting

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-$5k3.30-

Summaryinfo

A vulnerability, which was classified as problematic, was found in BookStackApp BookStack up to 26.05.3. This vulnerability affects unknown code of the component Drawing Upload Endpoint. Such manipulation leads to cross site scripting. This vulnerability is traded as CVE-2026-84695. The attack may be launched remotely. There is no exploit available.

Detailsinfo

A vulnerability was found in BookStackApp BookStack up to 26.05.3 and classified as problematic. Affected by this issue is some unknown functionality of the component Drawing Upload Endpoint. The manipulation with an unknown input leads to a cross site scripting vulnerability. Using CWE to declare the problem leads to CWE-79. The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users. Impacted is integrity. CVE summarizes:

BookStack before 26.05.4 contains a stored cross-site scripting vulnerability in the drawing upload endpoint that accepts unvalidated base64 content and stores it without content inspection. Attackers with editor permissions can upload SVG files containing scripts that execute in administrator browsers when accessed through the image gallery API without content-type validation or CSP headers.

The advisory is available at github.com. This vulnerability is handled as CVE-2026-84695 since 09/02/2026. The exploitation is known to be easy. The attack may be launched remotely. Successful exploitation requires user interaction by the victim. The technical details are unknown and an exploit is not available. This vulnerability is assigned to T1059.007 by the MITRE ATT&CK project.

Upgrading to version 26.05.4 eliminates this vulnerability.

If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Vendor

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 6.1
VulDB Meta Temp Score: 6.0

VulDB Base Score: 3.5
VulDB Temp Score: 3.4
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 8.7
CNA Vector (VulnCheck): 🔒

CVSSv2info

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

Exploitinginfo

Class: Cross site scripting
CWE: CWE-79 / CWE-94 / CWE-74
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: BookStack 26.05.4

Timelineinfo

09/02/2026 Advisory disclosed
09/02/2026 +0 days CVE reserved
09/02/2026 +0 days VulDB entry created
09/02/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: github.com
Status: Confirmed

CVE: CVE-2026-84695 (🔒)
GCVE (CVE): GCVE-0-2026-84695
GCVE (VulDB): GCVE-100-397994

Entryinfo

Created: 09/02/2026 03:30
Changes: 09/02/2026 03:30 (76)
Complete: 🔍
Cache ID: 216::103

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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