CVE-2021-47836Public exploitNetwork attack vector

Command execution via unsanitized Markdown rendering

Published Jan 16, 2026 · Updated Jan 16, 2026

Cross-site scripting in jersou Markdown Explorer 0.1.1 allows attackers to execute commands when a crafted Markdown file is opened. The preview path converts file or editor Markdown to HTML without sanitizing embedded event handlers, which can invoke Node.js child_process APIs in Electron. Exploitation requires a victim to open a supplied file or enter the payload, and commands run with that desktop user's privileges.

CVSS severity6.1
Medium
EPSS probability0.36%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Cross-site scripting in jersou Markdown Explorer 0.1.1 allows attackers to execute commands when a crafted Markdown file is opened. The preview path converts file or editor Markdown to HTML without sanitizing embedded event handlers, which can invoke Node.js child_process APIs in Electron. Exploitation requires a victim to open a supplied file or enter the payload, and commands run with that desktop user's privileges.

The record

CVE
CVE-2021-47836
Published
Jan 16, 2026
Updated
Jan 16, 2026
Vendor
jersou
Product
Markdown Explorer
Classifications
CWE-79, T1204.002
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jan 16, 2026CVE publishedPublication date reported by the CVE source.
  2. Jan 16, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=0.1.1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

jersou · Markdown Explorerversion=0.1.1

Published CVSS scores

6.1VulnCheckCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
5.1VulnCheckCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
T1204.002Malicious File

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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