CVE-2025-6492Public exploitNetwork attack vector

Application freeze via pathological Markdown regex backtracking

Published Jun 22, 2025 · Updated Jun 23, 2025

Inefficient regular expression complexity in MarkText 0.17.0 and 0.17.1 allows remote attackers to freeze the application via crafted Markdown. The getRecommendTitleFromMarkdownString function applies a heading-matching expression to the entire document and pathologically backtracks when a heading marker is followed by a very long run of spaces and a newline. No authentication or user interaction is required under the CNA assessment, and the bounded consequence is CPU exhaustion and an application freeze.

CVSS severity5.3
Medium
EPSS probability0.49%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Inefficient regular expression complexity in MarkText 0.17.0 and 0.17.1 allows remote attackers to freeze the application via crafted Markdown. The getRecommendTitleFromMarkdownString function applies a heading-matching expression to the entire document and pathologically backtracks when a heading marker is followed by a very long run of spaces and a newline. No authentication or user interaction is required under the CNA assessment, and the bounded consequence is CPU exhaustion and an application freeze.

The record

CVE
CVE-2025-6492
Published
Jun 22, 2025
Updated
Jun 23, 2025
Vendor
MarkText
Product
MarkText
Classifications
CWE-400, CWE-1333, T1499.004
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jun 22, 2025CVE publishedPublication date reported by the CVE source.
  2. Jun 23, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

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

  1. Affected versionversion=0.17.0
  2. Affected versionversion=0.17.1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

MarkText · MarkTextversion=0.17.0; version=0.17.1

Published CVSS scores

5.3VulDBCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
5.5VulDBCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P
5.0VulDBAV:N/AC:L/Au:N/C:N/I:N/A:P

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 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-400Uncontrolled Resource Consumption
CWE-1333Inefficient Regular Expression Complexity
T1499.004Application or System Exploitation

Public exploit references

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

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo