Name: CVE-2019-9900: Improper Neutralization of Special Elements in Output Used by a Downstream Component
Creator: Rapid7
Published: 2019-04-25T00:00:00.000Z
License: https://www.rapid7.com/legal/website-terms-of-use/
Keywords: CVE, CVE-2019-9900, CWE-74, CVSS 8.3, EPSS 0.00035

When parsing HTTP/1.x header values, Envoy 1.9.0 and before does not reject embedded zero characters (NUL, ASCII 0x0). This allows remote attackers crafting header values containing embedded NUL characters to potentially bypass header matching rules, gaining access to unauthorized resources.

CVSS Details

CVSS 3.1 Base Score: 8.3
CVSS 3.1 Vector: (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:L)
CVSS 3.0 Base Score: 6.5
CVSS 3.0 Vector: (CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:L/A:L)

Covered by Rapid7

Product	Vendor Advisory	Solution File	Added	Published
Freebsd	—	Upgrade istio	Apr 23, 2019	Apr 22, 2019
Vmware Photon_os	—	Use 'tdnf update' to upgrade all packages to the latest version.	Jan 20, 2025	Apr 25, 2019

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CVSS Details

Covered by Rapid7

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