shd101wyy Markdown Preview Enhanced up to 0.8.27 window.eval eval injection

Summaryinfo

A vulnerability was found in shd101wyy Markdown Preview Enhanced up to 0.8.27. It has been rated as critical. Affected by this issue is the function window.eval. The manipulation leads to eval injection. This vulnerability is listed as CVE-2026-50733. The attack may be initiated remotely. There is no available exploit. Upgrading the affected component is advised.

Detailsinfo

A vulnerability was found in shd101wyy Markdown Preview Enhanced up to 0.8.27. It has been rated as critical. This issue affects the function window.eval. The manipulation with an unknown input leads to a eval injection vulnerability. Using CWE to declare the problem leads to CWE-95. The product receives input from an upstream component, but it does not neutralize or incorrectly neutralizes code syntax before using the input in a dynamic evaluation call (e.g. "eval"). Impacted is confidentiality, integrity, and availability. The summary by CVE is:

Markdown Preview Enhanced before 0.8.28 parses WaveDrom diagrams by evaluating untrusted markdown content with eval(), allowing arbitrary JavaScript execution. The flaw affects every render path - the live preview (window.eval) and presentation mode plus HTML export (the bundled WaveDrom.ProcessAll()/eva() helpers) - and can also be triggered through a element injected via raw HTML in markdown. When a victim previews or exports a crafted markdown document, an attacker can execute arbitrary code, leading to arbitrary file write. Fixed in 0.8.28 by parsing with JSON5.parse() and sanitizing WaveDrom data scripts to inert strict JSON.

The weakness was presented by Neo. It is possible to read the advisory at github.com. The identification of this vulnerability is CVE-2026-50733 since 06/05/2026. The exploitation is known to be easy. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. It demands that the victim is doing some kind of user interaction. Technical details of the vulnerability are known, but there is no available exploit.

Upgrading to version 0.8.28 eliminates this vulnerability.

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

Vendor

• shd101wyy

Name

• Markdown Preview Enhanced

Version

• 0.8.0
• 0.8.1
• 0.8.2
• 0.8.3
• 0.8.4
• 0.8.5
• 0.8.6
• 0.8.7
• 0.8.8
• 0.8.9
• 0.8.10
• 0.8.11
• 0.8.12
• 0.8.13
• 0.8.14
• 0.8.15
• 0.8.16
• 0.8.17
• 0.8.18
• 0.8.19
• 0.8.20
• 0.8.21
• 0.8.22
• 0.8.23
• 0.8.24
• 0.8.25
• 0.8.26
• 0.8.27

CPE 2.3info

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CPE 2.2info

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