grimmory-tools grimmory up to 2.3.0 EPUB File cross site scripting

CVSS Meta Temp Score
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CTI Interest Score
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4.4$0-$5k0.00

Summaryinfo

A vulnerability described as problematic has been identified in grimmory-tools grimmory up to 2.3.0. This issue affects some unknown processing of the component EPUB File Handler. The manipulation results in cross site scripting. This vulnerability was named CVE-2026-42451. The attack may be performed from remote. There is no available exploit. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability, which was classified as problematic, was found in grimmory-tools grimmory up to 2.3.0. Affected is an unknown code block of the component EPUB File Handler. The manipulation with an unknown input leads to a cross site scripting vulnerability. CWE is classifying the issue as 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. This is going to have an impact on integrity. CVE summarizes:

Grimmory is a self-hosted digital library. Prior to version 2.3.1, a stored cross-site scripting (XSS) vulnerability in Grimmory's browser-based EPUB reader allows an attacker to embed arbitrary JavaScript in a crafted EPUB file. When a victim opens the book, the script executes in their browser with full access to the Grimmory application's session context. This can enable session token theft and account takeover, including administrative access if an administrator opens the affected book. This issue has been patched in version 2.3.1.

The advisory is shared for download at github.com. This vulnerability is traded as CVE-2026-42451 since 04/27/2026. The exploitability is told to be difficult. 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. The MITRE ATT&CK project declares the attack technique as T1059.007.

Upgrading to version 2.3.1 eliminates this vulnerability. The upgrade is hosted for download at github.com.

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Productinfo

Vendor

Name

Version

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 4.4
VulDB Meta Temp Score: 4.4

VulDB Base Score: 2.6
VulDB Temp Score: 2.5
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 6.3
CNA Vector (GitHub_M): 🔒

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: Partially
Local: Yes
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

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: grimmory 2.3.1

Timelineinfo

04/27/2026 CVE reserved
05/09/2026 +12 days Advisory disclosed
05/09/2026 +0 days VulDB entry created
05/09/2026 +0 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: GHSA-frv6-5wq5-9p24
Status: Confirmed

CVE: CVE-2026-42451 (🔒)
GCVE (CVE): GCVE-0-2026-42451
GCVE (VulDB): GCVE-100-362388

Entryinfo

Created: 05/09/2026 06:57
Changes: 05/09/2026 06:57 (66)
Complete: 🔍
Cache ID: 216::103

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