CVE-2024-23326 - CVE House
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Status published Medium CVE-2024-23326

Envoy incorrectly accepts HTTP 200 response for entering upgrade mode

Vulnerability Description

Envoy is a cloud-native, open source edge and service proxy. A theoretical request smuggling vulnerability exists through Envoy if a server can be tricked into adding an upgrade header into a response. Per RFC https://www.rfc-editor.org/rfc/rfc7230#section-6.7 a server sends 101 when switching protocols. Envoy incorrectly accepts a 200 response from a server when requesting a protocol upgrade, but 200 does not indicate protocol switch. This opens up the possibility of request smuggling through Envoy if the server can be tricked into adding the upgrade header to the response.

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
Vulnerable Versions:
>= 1.13.0, <= 1.30.1, >= 1.29.0, <= 1.29.4, >= 1.28.0, <= 1.28.3, <= 1.27.5

Timeline

Official Publish: June 4th, 2024
Last Modified: August 1st, 2024
Added to House: July 22nd, 2026

CVSS Vectors

V3: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N

Weaknesses (CWE)

CWE-391

MITRE ATT&CK TTPs

No associated TTPs found for this vulnerability.