Regular expression Denial of Service in dialog plugin
Published: January 26, 2021
SECURITY IDENTIFIERS
- CVE: CVE-2021-26271 (NVD)
- GHSA: GHSA-f6rf-9m92-x2hh
- Vendor Advisory: https://github.com/ckeditor/ckeditor4/blob/master/CHANGES.md#ckeditor-416
GEM
SEVERITY
CVSS v3.x: 6.5 (Medium)
PATCHED VERSIONS
>= 5.1.2
DESCRIPTION
Affected packages
The vulnerability has been discovered and fixed in the dialog plugin. Packages indirectly affected by the issue having dialog plugin dependency:
Impact
A potential vulnerability has been discovered in CKEditor 4 dialog plugin. The vulnerability allowed to abuse a dialog input validator regular expression, which could cause a significant performance drop resulting in a browser tab freeze. It affects all users using the CKEditor 4 plugins listed above at version < 4.18.0.
Patches
The problem has been recognized and patched. The fix will be available in version 4.18.0.
For more information
Email us at security@cksource.com if you have any questions or comments about this advisory.
Acknowledgements
This issue was discovered by the CKEditor 4 team during our regular security audit.