Use-after-free when parsing CSS in Internet Explorer

1) Use-after-free

EUVDB-ID: #VU5545

Risk: Critical

CVSSv4.0: 8.6 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:A/U:Red]

CVE-ID: CVE-2010-3962

CWE-ID: CWE-416 - Use After Free

Exploit availability: Yes

Description

The vulnerability allows a remote attacker to execute arbitrary code on the target system.

The vulnerability exists due to use-after-free error when processing CSS token sequences and the clip attribute. A remote attacker can create a specially crafted HTML page, trick the victim into visiting it, cause memory corruption and execute arbitrary code on the target system.

Successful exploitation of this vulnerability may result in complete compromise of vulnerable system.

Note: this vulnerability is being actively exploited.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

Microsoft Internet Explorer: 6 - 8

CPE2.3

• cpe:2.3:a:microsoft:microsoft_internet_explorer:6:*:*:*:*:*:*:*
• cpe:2.3:a:microsoft:microsoft_internet_explorer:7:*:*:*:*:*:*:*
• cpe:2.3:a:microsoft:microsoft_internet_explorer:8:*:*:*:*:*:*:*

External links

https://technet.microsoft.com/library/security/2458511
https://technet.microsoft.com/library/security/ms10-090
https://www.symantec.com/connect/blogs/new-ie-0-day-used-targeted-attacks
https://security.bkav.com/home/-/blogs/new-ie-zero-day-vulnerability-cve-2010-3962-/normal

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

How the attacker can exploit this vulnerability?

The attacker would have to trick the victim to visit a specially crafted website.

Is there known malware, which exploits this vulnerability?

Yes. This vulnerability is being exploited in the wild.