CVE-2019-18860

MEDIUMNVD 6.16.1—

6.1

Squid before 4.9, when certain web browsers are used, mishandles HTML in the host (aka hostname) parameter to cachemgr.cgi.

CVSS v3: 6.1
EG Score: 6.1(medium)
EPSS: 89.1%
KEV: Not listed

Published

March 20, 2020

Last Modified

November 5, 2025

References (15)

cve@mitrehttp://lists.opensuse.org/opensuse-security-announce/2020-05/msg00018.html
cve@mitrehttps://github.com/squid-cache/squid/pull/504
cve@mitrehttps://github.com/squid-cache/squid/pull/505
cve@mitrehttps://lists.debian.org/debian-lts-announce/2020/07/msg00009.html
cve@mitrehttps://usn.ubuntu.com/4356-1/
cve@mitrehttps://www.debian.org/security/2020/dsa-4732
af854a3a-2127-422b-91ae-364da2661108http://lists.opensuse.org/opensuse-security-announce/2020-05/msg00018.html
af854a3a-2127-422b-91ae-364da2661108http://www.openwall.com/lists/oss-security/2025/11/04/7
af854a3a-2127-422b-91ae-364da2661108http://www.openwall.com/lists/oss-security/2025/11/05/1
af854a3a-2127-422b-91ae-364da2661108http://www.openwall.com/lists/oss-security/2025/11/05/7
af854a3a-2127-422b-91ae-364da2661108https://github.com/squid-cache/squid/pull/504
af854a3a-2127-422b-91ae-364da2661108https://github.com/squid-cache/squid/pull/505
af854a3a-2127-422b-91ae-364da2661108https://lists.debian.org/debian-lts-announce/2020/07/msg00009.html
af854a3a-2127-422b-91ae-364da2661108https://usn.ubuntu.com/4356-1/
af854a3a-2127-422b-91ae-364da2661108https://www.debian.org/security/2020/dsa-4732

Patch Availability(2)

Vendor / Ecosystem	Fixed in / Patch	Released	Source
ubuntu	squidclient (4.8-1ubuntu2.3) @ eoan	2026-05-27	ubuntu
redhat	squid:4-8030020200828070549.30b713e6	2020-11-04	redhat

Patches are aggregated from vendor advisories (Red Hat, Microsoft, Cisco, GitHub) and package ecosystems (OSV, GHSA). Multiple rows for the same upstream release have been deduplicated.

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

CWE-74Improper Neutralization of Special Elements in Output Used by a Downstream Component (Injection)

All Vendor Advisories

(2)

Every vendor that published an advisory referencing this CVE — pulled from our cve_vendor_advisories aggregation. Click any row for the vendor's original advisory page.

Data Freshness Timeline

(refreshed 10× in last 7d / 17× in last 30d)

Every time one of our enrichment pipelines (NVD, MITRE cvelistV5, EPSS, CISA KEV, GHSA, OSV, vendor advisories) ran against this CVE. Most recent first.

2026-06-02 20:11 UTCepss_batch
2026-06-02 20:11 UTCepss_batch
2026-06-01 13:50 UTCepss_batch
2026-06-01 13:50 UTCepss_batch
2026-05-31 22:29 UTCepss_batch
2026-05-31 22:29 UTCepss_batch
2026-05-31 00:14 UTCepss_batch
2026-05-31 00:14 UTCepss_batch
2026-05-29 13:42 UTCepss_batch
2026-05-28 13:43 UTCepss_batch
2026-05-27 13:38 UTCepss_batch
2026-05-27 06:09 UTCEG score recompute
2026-05-27 06:09 UTCVendor advisory
2026-05-27 06:09 UTCGHSA enrichment
2026-05-26 07:17 UTCepss_batch
2026-05-26 07:17 UTCepss_batch
2026-05-26 07:17 UTCepss_batch

Frequently asked(5)

What is CVE-2019-18860?

CVE-2019-18860 is a medium vulnerability published on March 20, 2020. Squid before 4.9, when certain web browsers are used, mishandles HTML in the host (aka hostname) parameter to cachemgr.cgi.

When was CVE-2019-18860 disclosed?

CVE-2019-18860 was first published in the National Vulnerability Database on March 20, 2020, with the most recent update on November 5, 2025. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.

Is CVE-2019-18860 actively exploited?

CVE-2019-18860 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 89.1% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.

What is the CVSS score of CVE-2019-18860?

CVE-2019-18860 has a CVSS v3 base score of 6.1 (NVD).

How do I remediate CVE-2019-18860?

Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2019-18860, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

See which npm, PyPI, Go, and Maven packages are affected by CVE-2019-18860

Explore →

Is Your Infrastructure Affected by CVE-2019-18860?

EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.

Start Free Scan →Browse All CVEs

CVE-2019-18860

Published

Last Modified

References (15)

Patch Availability(2)

Weakness Classification(1)

All Vendor Advisories

Data Freshness Timeline

Frequently asked(5)

Dependency Blast Radius

Is Your Infrastructure Affected by CVE-2019-18860?

Same vendor

Same CWE

CVE-2019-18860

📅 Published

🔄 Last Modified

🔗 References (15)

Patch Availability(2)

Weakness Classification(1)

All Vendor Advisories

Data Freshness Timeline

❓ Frequently asked(5)

Dependency Blast Radius

Is Your Infrastructure Affected by CVE-2019-18860?

🔗 Related CVEs(same vendor + same CWE)

Same vendor

Same CWE

Published

Last Modified

References (15)

Frequently asked(5)

Related CVEs(same vendor + same CWE)