CVE-2019-9900 - CVE House
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Status published Medium CVE-2019-9900

When parsing HTTP/1.x header values, Envoy 1.9.0 and before does...

Vulnerability Description

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.

Impact Analysis

Refer to official advisory for detailed impact metrics.

Remediation

Ensure systems are updated to the latest vendor-supplied patch levels.

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Credits & Attribution

No credits recorded in the NVD database.

References

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Affected Vendor

Affected Software

envoy, openshift service mesh
Vulnerable Versions:
0

Timeline

Official Publish: April 25th, 2019
Last Modified: August 4th, 2024
Added to House: July 20th, 2026

CVSS Vectors

V3: CVSS:3.0/AC:H/AV:N/A:L/C:L/I:L/PR:N/S:C/UI:N

Weaknesses (CWE)

No CWE data available

MITRE ATT&CK TTPs

No associated TTPs found for this vulnerability.