Input validation error in CKEditor - CVE-2021-26271
Published: January 27, 2021
Vulnerability identifier: #VU50055
CSH Severity: Low
CVSS v4.0: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:U/U:Clear
CVE-ID: CVE-2021-26271
CWE-ID: CWE-20
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vendor: CKSource
Affected software:
CKEditor
CKEditor
Detailed vulnerability description
The vulnerability allows a remote attacker to perform a regular expression denial of service (ReDoS) attack.
The vulnerability exists due to insufficient validation of user-supplied input. A remote attacker can trick the victim to paste a specially crafted text into the Styles input of specific dialogs (in the Advanced Tab for Dialogs plugin) and perform a regular expression denial of service (ReDoS) attack.
How to mitigate CVE-2021-26271
Install updates from vendor's website.