CVE-2025-6493 Details
Description
A weakness has been identified in CodeMirror up to 5.65.20. Affected is an unknown function of the file mode/markdown/markdown.js of the component Markdown Mode. This manipulation causes inefficient regular expression complexity. It is possible to initiate the attack remotely. The exploit has been made available to the public and could be exploited. Upgrading to version 6.0 is able to address this issue. You should upgrade the affected component. Not all code samples mentioned in the GitHub issue can be found. The repository mentions, that "CodeMirror 6 exists, and is [...] much more actively maintained."
A denial-of-service vulnerability has been identified in CodeMirror versions through 5.17.0, specifically within the Markdown mode component. The issue arises from certain regular expressions that exhibit inefficient complexity, allowing specially crafted input to cause catastrophic backtracking. This exploitation can freeze the application or significantly degrade performance. The vulnerability can be triggered remotely in both browser and server-side environments that use CodeMirror's Markdown mode.
Metrics
CVSS 4.0 Severity and Vector Strings:
VolerionCVSS 3.x Severity and Vector Strings:
No data available for CVSS Version 2.0 on this CVE.
Volerion
Assessed Jun 22, 2025CISA-ADP
Assessed Jun 23, 2025References to Advisories, Solutions, and Tools
By selecting these links, you will be leaving this site. These are references gathered from the official CVE record and are not endorsed by Volerion.
| URL | Source(s) | Tag(s) |
|---|---|---|
| https://github.com/codemirror/codemirror5/issues/7128 | [email protected] | ExploitIssue TrackingTechnical DescriptionVendor |
| https://vuldb.com/?ctiid.313610 | [email protected] | AdvisoryExploit |
| https://vuldb.com/?id.313610 | [email protected] | AdvisoryExploitPartial Content |
| https://vuldb.com/?submit.598875 | [email protected] | Technical Description |
Weakness Enumeration
| CWE-ID | CWE Name | Source |
|---|---|---|
| CWE-1333 | Inefficient Regular Expression Complexity | [email protected] |
| CWE-400 | Uncontrolled Resource Consumption | [email protected] |
Affected Products
| Product | Versions |
|---|---|
| CodeMirror | <= 5.17.0 (semver) |
CPE
Remediation
| |
Change History
4 change records found show changes
| Date | Action | Recorded By |
|---|---|---|
| Jun 17, 2026 | CVE Modified | [email protected] |
| Jun 17, 2026 | CVE Modified | CISA-ADP |
| Sep 29, 2025 | CVE Modified | [email protected] |
| Jun 22, 2025 | New CVE Received | [email protected] |