CVE-2018-19131 — Squid before 4

Squid before 4.4 has XSS via a crafted X.509 certificate during HTTP(S) error page generation for certificate errors.

01What is this vulnerability?

Squid before 4.4 has XSS via a crafted X.509 certificate during HTTP(S) error page generation for certificate errors.

02Affected products

Vendor	Product	Versions
n	a / n/a	n/a

03Active exploitation status

Not currently listed on the CISA Known Exploited Vulnerabilities (KEV) catalog. EPSS is the best forward-looking signal — see the EPSS row above.

04Recommended remediation

• Patch to a fixed version listed in the vendor advisory (see references below).
• Mitigate with WAF rules, network egress filters, or feature flags where the patch is not yet available.
• Hunt historical logs for exploitation indicators — see Detection signatures below.

05Technical details

For the full vendor write-up, exploit chains, and reference implementations, see the references list in section 09.

06Detection signatures

Ask SARA in chat to draft a starting detection for this CVE in your stack of choice.

07Related CVEs

No directly-cited follow-up CVEs in the KB record for this advisory. The references list in section 09 carries the vendor cross-references.

08Timeline

• Published: 2018-11-09T11:00:00.000Z
• Last modified: 2024-09-16T18:33:29.179Z

09References

• www.squid-cache.org — http://www.squid-cache.org/Versions/v5/changesets/squid-5-6feeb15ff312f3e145763a…
• www.squid-cache.org — http://www.squid-cache.org/Advisories/SQUID-2018_4.txt
• github.com — https://github.com/squid-cache/squid/pull/306