Null Byte Injection in Envoy HTTP/1.x Header Parsing

Null Byte Injection in Envoy HTTP/1.x Header Parsing

CVE-2019-9900 · HIGH Severity

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:L

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.

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