Vulnerability identifier: #VU26561

Vulnerability risk: Low

CVSSv3.1: 4.7 [CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N/E:U/RL:O/RC:C]

CVE-ID: CVE-2020-5283

CWE-ID: CWE-79

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
ViewVC
Web applications / Modules and components for CMS

Vendor: ViewVC

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 in CVS repository in "show_subdir_lastmod" support. A remote authenticated 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 vulnerable 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.

Mitigation
Install update from vendor's website.

Vulnerable software versions

ViewVC: 1.2.0, 1.1.0 - 1.1.27, 1.0.0 - 1.0.14, 0.9.0 - 0.9.4, 0.8.0, 0.7.0, 0.6.0, 0.5.0, 0.4.0, 0.3.0

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External links
http://github.com/viewvc/viewvc/commit/ad0f966e9a997b17d853a6972ea283d4dcd70fa8
http://github.com/viewvc/viewvc/issues/211
http://github.com/viewvc/viewvc/security/advisories/GHSA-xpxf-fvqv-7mfg

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote authenticated user via the Internet.

Is there known malware, which exploits this vulnerability?

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