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."
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| — | CodeMirror | 5.65.0, 5.65.1, 5.65.2, 5.65.3, 5.65.4, 5.65.5, 5.65.6, 5.65.7, 5.65.8, 5.65.9, 5.65.10, 5.65.11, 5.65.12, 5.65.13, 5.65.14, 5.65.15, 5.65.16, 5.65.17, 5.65.18, 5.65.19, 5.65.20 | 6.0 |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | codemirror-js | No fix yet | — |
| Debian 13 | codemirror-js | No fix yet | — |
| Debian 12 | codemirror-js | No fix yet | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.10 | codemirror-js | No fix yet | — |
| Ubuntu 26.04 LTS | codemirror-js | No fix yet | — |
| Ubuntu 25.10 | codemirror-js | No fix yet | — |
| Ubuntu 24.04 LTS | codemirror-js | No fix yet | — |
| Ubuntu 22.04 LTS | codemirror-js | No fix yet | — |
Show 3 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 20.04 LTS | codemirror-js | No fix yet | — |
| Ubuntu 18.04 LTS | codemirror-js | No fix yet | — |
| Ubuntu 16.04 LTS | codemirror-js | No fix yet | — |
Advisories 1
- WID-SEC-2025-2088 SOS GmbH JobScheduler: Mehrere Schwachstellen BSI CERT-Bund (WID) · Sep 18, 2025
References
- VDB-313610 | CodeMirror Markdown Mode markdown.js redos vdb-entry technical-description
- VDB-313610 | CTI Indicators (IOB, IOC, TTP, IOA) signature permissions-required
- Submit #598875 | codemirror codemirror5 <=5.17.0 Inefficient Regular Expression Complexity third-party-advisory
- https://github.com/codemirror/codemirror5/issues/7128 exploit issue-tracking