Zero-day vulnerability in Windows

Buffer overflow

The vulnerability was reported by ESET in March 2018. The attackers used this vulnerability along with double free error in Adobe Acrobat CVE-2018-4990.

Known malware:

Win32/Exploit.CVE-2018-8120.A trojan (ESET)

Vulnerability details

Advisory: SB2018050813 - Privilege escalation in Microsoft Windows win32k.sys driver

Vulnerable component: Windows

CVE-ID: CVE-2018-8120

CVSSv3 score: CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H/E:U/RL:O/RC:C

CWE-ID: CWE-119 - Improper Restriction of Operations within the Bounds of a Memory Buffer


The vulnerability allows a local user to escalate privileges on the system.

The vulnerability exists due to boundary error in win32k.sys driver. A local user can execute arbitrary code with SYSTEM privileges.

Note: this vulnerability is being actively exploited in limited targeted attacks.

Latest references in media:

- Patch Tuesday, May 2018 [2018-05-20 07:26:36]

- Signal bugs, car hack antics, the Adobe flaw you may have missed, and much more [2018-05-19 10:42:32]

- Malicious PDF Leads to Discovery of Adobe Reader, Windows Zero-Days [2018-05-16 14:43:31]

- Mysterious hackers ingenuously reveal two Zero-Days to security community [2018-05-16 13:56:15]

- Shadowy Hackers Accidentally Reveal Two Zero-Days to Security Researchers [2018-05-15 23:30:09]

- Patch now! Microsoft and Adobe release critical security updates [2018-05-09 18:30:02]

- Windows critical flaw: This security bug is under attack right now, says Microsoft | ZDNet [2018-05-09 15:30:08]

- Microsoft Patches Two Zero-Day Flaws this Month [2018-05-09 12:41:56]

- Microsoft Patch Tuesday for May Includes Updates for Actively-Exploited Vulnerabilities [2018-05-09 11:00:33]

- May 2018 Patch Tuesday: Microsoft fixes 2 zero-day flaws reportedly exploited by APT group [2018-05-09 10:16:42]

- Patch Tuesday, May 2018 [2018-05-09 09:13:35]

- Microsoft's May 2018 Patch Tuesday update fixes a total 21 critical vulnerabilities, including two flaws that have been under active attack since last month. [2018-05-09 08:30:07]

- It's 2018, and a webpage can still pwn your Windows PC тАУ and apps can escape Hyper-V [2018-05-09 03:51:18]

- Microsoft's Patch Tuesday Fixes Two CVEs Under Active Attack [2018-05-08 23:20:01]

- May Patch Tuesday Fixes Two Bugs Under Active Attack [2018-05-08 22:55:21]

- Microsoft Patches Two Windows Zero-Day Vulnerabilities [2018-05-08 22:04:29]

- Microsoft May 2018 Patch Tuesday Fixes 67 Security Issues, Including IE Zero-Day [2018-05-08 20:44:45]

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