CVE-2018-19131 Cross-site scripting in n/a
An attacker can execute arbitrary scripts in the victim's browser via a crafted X.509 certificate during Squid proxy error page generation.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- Available
What is CVE-2018-19131?
CVE-2018-19131 is a medium-severity cross-site scripting vulnerability in Squid-Cache Squid, published on 9 Nov 2018. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Official description
Squid before 4.4 has XSS via a crafted X.509 certificate during HTTP(S) error page generation for certificate errors.
Weakness: CWE-79
Which versions are affected by CVE-2018-19131?
It affects 1 product.
Linux distribution packages (2)
squid3 SUSE:Linux Enterprise Server 11 SP4 | All versions | 3.1.23-8.16.37.9.1 |
squid3 SUSE:Linux Enterprise Server for SAP Applications 11 SP4 | All versions | 3.1.23-8.16.37.9.1 |
Products include Squid-Cache Squid.
How do I fix CVE-2018-19131?
Upgrade to a fixed version.
Escape output for the context it lands in and set a strict Content Security Policy. Upgrading the affected component is the real fix. More about Cross-site scripting.
Is CVE-2018-19131 being exploited?
There is no known exploitation of CVE-2018-19131 in the wild and no public exploit code.
Public exploit code: 1 proofs of concept on GitHub.
Other vulnerabilities in Squid-Cache Squid
- CVE-2025-62168 Squid vulnerable to information disclosure via authentication credential leakage in error handling
- CVE-2025-54574 Squid's URN Handling can lead to Buffer Overflow
- CVE-2026-33526 Squid vulnerable to Denial of Service in ICP Request handling
- CVE-2026-32748 Squid has Denial of Service in ICP Response handling
- CVE-2023-50269 SQUID-2023:10 Denial of Service in HTTP Request parsing
Sources
Also known as CVE-2018-1000819, DEBIAN-CVE-2018-19131, GHSA-jr78-3r97-gpxf, SUSE-SU-2018:3790-1.