Vulnerability identifier: #VU15896
Vulnerability risk: Low
CVSSv3.1: 4.2 [CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:L/I:L/A:N/E:P/RL:O/RC:C]
CVE-ID:
CWE-ID:
CWE-79
Exploitation vector: Network
Exploit availability: Yes
Vulnerable software:
Squid
Server applications /
IDS/IPS systems, Firewalls and proxy servers
Vendor: Squid-cache.org
Description
The vulnerability allows a remote attacker to perform cross-site scripting (XSS) attacks.
The vulnerability exists due to insufficient sanitization of user-supplied data when processing a specially crafted X.509 certificate during HTTP(S) error page generation for certificate errors. A remote attacker can trick the victim to follow a specially 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
Squid: 4.0.1 - 4.3
External links
http://www.squid-cache.org/Advisories/SQUID-2018_4.txt
http://www.squid-cache.org/Versions/v5/changesets/squid-5-6feeb15ff312f3e145763adf8d234ed6a0b3f11d.patch
http://github.com/squid-cache/squid/pull/306
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. However, proof of concept for this vulnerability is available.