#VU51747 Universal cross-site scripting in WebKitGTK+ and WPE WebKit - CVE-2021-1879

Vulnerability identifier: #VU51747

Vulnerability risk: High

CVSSv4.0: 5.1 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N/E:A/U:Amber]

CVE-ID: CVE-2021-1879

CWE-ID: CWE-79

Exploitation vector: Network

Exploit availability: Yes

Vulnerable software:
WebKitGTK+
Server applications / Frameworks for developing and running applications
WPE WebKit
Server applications / Frameworks for developing and running applications

Vendor: WebKitGTK

Description

The disclosed vulnerability allows a remote attacker to perform cross-site scripting (XSS) attacks.

The vulnerability exists due to insufficient sanitization of user-supplied data within the WebKit engine. A remote attacker can trick the victim to follow a specially crafted link and execute arbitrary HTML and script code in user's browser in context of arbitrary website.

Successful exploitation of this vulnerability may allow a remote attacker to steal potentially sensitive information, change appearance of the web page, perform phishing and drive-by-download attacks.

Note, the vulnerability is being actively exploited in the wild.

Mitigation
Install update from vendor's website.

Vulnerable software versions

WebKitGTK+: 2.0.0 - 2.31.91

WPE WebKit: 2.19.93 - 2.31.91

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External links
https://support.apple.com/en-us/HT212256
https://support.apple.com/en-us/HT212257

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Q & A

Can this vulnerability be exploited remotely?

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

Is there known malware, which exploits this vulnerability?

Yes. This vulnerability is being exploited in the wild.