What is the CVSS score of CVE-2020-26211?

CVE-2020-26211 has a CVSS 3.1 base score of 8.7 (High). CVSS vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:N. EPSS exploitation probability: 1.1%.

Is there a patch available for CVE-2020-26211?

Yes, a patch is available for CVE-2020-26211. Update the affected software to the latest version immediately.

Bookstack CVE-2020-26211

HIGH

Cross-site Scripting (XSS) (CWE-79)

2020-11-03 security-advisories@github.com

XSS Bookstack

8.7

CVSS 3.1 · NVD

Severity by source

NVD PRIMARY

8.7 HIGH

AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:N

Primary rating from NVD · only source for this CVE.

CVSS VectorNVD

CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:N

Attack Vector

Network

Attack Complexity

Low

Privileges Required

Low

User Interaction

Required

Scope

Changed

Confidentiality

High

Integrity

High

Availability

None

Lifecycle Timeline

CVE Published

Nov 03, 2020 - 21:15 nvd

HIGH 8.7

DescriptionNVD

In BookStack before version 0.30.4, a user with permissions to edit a page could insert JavaScript code through the use of javascript: URIs within a link or form which would run, within the context of the current page, when clicked or submitted. Additionally, a user with permissions to edit a page could insert a particular meta tag which could be used to silently redirect users to a alternative location upon visit of a page. Dangerous content may remain in the database but will be removed before being displayed on a page. If you think this could have been exploited the linked advisory provides a SQL query to test. As a workaround without upgrading, page edit permissions could be limited to only those that are trusted until you can upgrade although this will not address existing exploitation of this vulnerability. The issue is fixed in BookStack version 0.30.4.

AnalysisAI

In BookStack before version 0.30.4, a user with permissions to edit a page could insert JavaScript code through the use of javascript: URIs within a link or form which would run, within the context. Rated high severity (CVSS 8.7), this vulnerability is remotely exploitable, low attack complexity. This Cross-Site Scripting (XSS) vulnerability could allow attackers to inject malicious scripts into web pages viewed by other users.

Technical ContextAI

This vulnerability is classified as Cross-Site Scripting (XSS) (CWE-79), which allows attackers to inject malicious scripts into web pages viewed by other users. In BookStack before version 0.30.4, a user with permissions to edit a page could insert JavaScript code through the use of javascript: URIs within a link or form which would run, within the context of the current page, when clicked or submitted. Additionally, a user with permissions to edit a page could insert a particular meta tag which could be used to silently redirect users to a alternative location upon visit of a page. Dangerous content may remain in the database but will be removed before being displayed on a page. If you think this could have been exploited the linked advisory provides a SQL query to test. As a workaround without upgrading, page edit permissions could be limited to only those that are trusted until you can upgrade although this will not address existing exploitation of this vulnerability. The issue is fixed in BookStack version 0.30.4. Affected products include: Bookstackapp Bookstack. Version information: version 0.30.4.

RemediationAI

A vendor patch is available. Apply the latest security update as soon as possible. Sanitize all user input, use Content-Security-Policy headers, encode output contextually (HTML, JS, URL). Use frameworks with built-in XSS protection.