CVE-2025-66287 is a classic buffer overflow vulnerability in WebKitGTK that occurs due to buffer copy operations without checking the size of input. This improper memory handling can lead to unexpected process crashes when malicious web content is processed. The vulnerability has a CVSS 3.1 base score of 8.8, indicating high impact with network attack vector, low attack complexity, no privileges required, user interaction required, and high confidentiality, integrity, and availability impacts. Red Hat advisories RHSA-2025:22789 and RHSA-2025:22790 confirm the issue and provide security updates for webkit2gtk3 packages in Red Hat Enterprise Linux 8 and 9. The advisories list this CVE among multiple WebKitGTK vulnerabilities fixed in the updates.

Successful exploitation of this vulnerability can cause an unexpected process crash, resulting in denial of service. The CVSS score indicates potential for high confidentiality, integrity, and availability impact, but the primary documented impact is process crash due to memory corruption. There are no known exploits in the wild at this time.

Official security updates are available from Red Hat for webkit2gtk3 packages in Red Hat Enterprise Linux 8 and 9. Users should apply these updates promptly to remediate the vulnerability. Refer to Red Hat advisories RHSA-2025:22789 and RHSA-2025:22790 and the update instructions at https://access.redhat.com/articles/11258 for detailed patching guidance. No additional mitigation actions are specified or required beyond applying the official patches.