US-CERT is aware of public reports of the existence of fraudulent SSL certificates. These fraudulent SSL certificates could be used by an attacker to masquerade as a trusted website. Multiple web browser vendors have provided updates to recognize and block these fraudulent SSL certificates.

Mozilla has updated Firefox 4.0, 3.6, and 3.5. Additional information can be found in the Mozilla Security Blog.

Microsoft has released updates for various platforms in Microsoft Knowledge Base Article 2524375. Additional information can be found in Microsoft Security Advisory 2524375.

US-CERT encourages users and administrators to apply any necessary updates to help mitigate the risks. US-CERT will provide additional information as it becomes available.

Read more: US-CERT Current Activity