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CVE-2019-18802
An issue was discovered in Envoy 1.12.0. An untrusted remote client may send an HTTP header (such as Host) with whitespace after the…
Critical9.8EPSS 2.5%
- Published
- Updated
- Reserved
- Assigned by
- mitre
Description
An issue was discovered in Envoy 1.12.0. An untrusted remote client may send an HTTP header (such as Host) with whitespace after the header content. Envoy will treat "header-value " as a different string from "header-value" so for example with the Host header "example.com " one could bypass "example.com" matchers.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| NVDNVD · Modified | 3.1 | Critical9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
- EPSS (exploitation in 30 days)
- 2.5% · top 16% of all CVEs (5 Nov 2026)
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The list uses the assigner's score when there is one, then CISA's, then NVD's: Critical 9.8.
Weakness
- n/a
Affected products
n/a
- affected n/a
References (5)
- https://github.com/envoyproxy/envoy/commits/master (opens in a new tab)x_refsource_MISCx_transferred
- https://groups.google.com/forum/#%21forum/envoy-users (opens in a new tab)x_refsource_MISCx_transferred
- https://blog.envoyproxy.io (opens in a new tab)x_refsource_MISCx_transferred
- https://github.com/envoyproxy/envoy/security/advisories/GHSA-356m-vhw2-wcm4 (opens in a new tab)x_refsource_MISCx_transferred
- openSUSE-SU-2020:0379 (opens in a new tab)vendor-advisoryx_refsource_SUSEx_transferred
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2019-18802)Record last updated .