#VU59663 Cross-site scripting in GNOME Web (Epiphany) - CVE-2021-45086

Vulnerability identifier: #VU59663

Vulnerability risk: Medium

CVSSv4.0: 1.2 [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:U/U:Green]

CVE-ID: CVE-2021-45086

CWE-ID: CWE-79

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
GNOME Web (Epiphany)
Client/Desktop applications / Web browsers

Vendor: Gnome Development Team

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, because a server's suggested_filename is used as the pdf_name value in PDF.js. A remote attacker can and execute arbitrary HTML and script code in user's browser in context of vulnerable website.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

GNOME Web (Epiphany): 40.0 - 40.3, 41.0

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External links
https://gitlab.gnome.org/GNOME/epiphany/-/merge_requests/1045
https://gitlab.gnome.org/GNOME/epiphany/-/issues/1612
https://www.debian.org/security/2022/dsa-5042

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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?

No. We are not aware of malware exploiting this vulnerability.