CVE-2019-20800

CRITICALNVD 9.89.8—

9.8

In Cherokee through 1.2.104, remote attackers can trigger an out-of-bounds write in cherokee_handler_cgi_add_env_pair in handler_cgi.c by sending many request headers, as demonstrated by a GET request with many "Host: 127.0.0.1" headers.

CVSS v3: 9.8
EG Score: 9.8(medium)
EPSS: 80.2%
KEV: Not listed

Published

May 18, 2020

Last Modified

November 21, 2024

Advisory Details (3)

Auto-updated May 27, 2026

🔬 Proof of concept available. No patch confirmed yet.

generic

Cherokee: Multiple vulnerabilities (GLSA 202012-09) — Gentoo security

https://security.gentoo.org/glsa/202012-09

generic🟡 PoC Available

Security Audits, Penetration Tests, Security Awareness - LogicalTrust - [EN] A-Z: Cherokee

https://logicaltrust.net/blog/2019/11/cherokee.html

generic

CGI Handler too many headers · Issue #1224 · cherokee/webserver · GitHub

https://github.com/cherokee/webserver/issues/1224

Weakness Classification(1)

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

CWE-787Out-of-bounds Write

Data Freshness Timeline

(refreshed 16× in last 7d / 20× 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.

2026-06-06 13:45 UTCepss_batch
2026-06-06 13:45 UTCepss_batch
2026-06-05 22:45 UTCepss_batch
2026-06-05 22:45 UTCepss_batch
2026-06-05 06:08 UTCepss_batch
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2026-06-04 13:10 UTCepss_batch
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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
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2026-05-31 00:14 UTCepss_batch
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2026-05-29 13:42 UTCepss_batch
2026-05-28 13:43 UTCepss_batch
2026-05-27 13:38 UTCepss_batch
2026-05-27 03:32 UTCEG score recompute

Frequently asked(5)

What is CVE-2019-20800?

CVE-2019-20800 is a critical vulnerability published on May 18, 2020. In Cherokee through 1.2.104, remote attackers can trigger an out-of-bounds write in cherokeehandlercgiaddenvpair in handlercgi.c by sending many request headers, as demonstrated by a GET request with many "Host: 127.0.0.1" headers.

When was CVE-2019-20800 disclosed?

CVE-2019-20800 was first published in the National Vulnerability Database on May 18, 2020, with the most recent update on November 21, 2024. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.

Is CVE-2019-20800 actively exploited?

CVE-2019-20800 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 80.2% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.

What is the CVSS score of CVE-2019-20800?

CVE-2019-20800 has a CVSS v3 base score of 9.8 (NVD).

How do I remediate CVE-2019-20800?

Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2019-20800, 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

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CVE-2019-20800

📅 Published

🔄 Last Modified

📋 Advisory Details (3)