CVE-2023-35944 Envoy vulnerable to incorrect handling of HTTP requests and responses with mixed case schemes

2023-07-2518:35:59

CWE-20

GitHub_M

www.cve.org

cve-2023-35944

envoy

http/2

vulnerable

case-sensitive

schemes

8.2 High

CVSS3

Attack Vector

NETWORK

Attack Complexity

LOW

Privileges Required

NONE

User Interaction

NONE

Scope

UNCHANGED

Confidentiality Impact

HIGH

Integrity Impact

LOW

Availability Impact

NONE

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

9.1 High

AI Score

Confidence

High

0.001 Low

EPSS

Percentile

20.9%

JSON

Envoy is an open source edge and service proxy designed for cloud-native applications. Envoy allows mixed-case schemes in HTTP/2, however, some internal scheme checks are case-sensitive. Prior to versions 1.27.0, 1.26.4, 1.25.9, 1.24.10, and 1.23.12, this can lead to the rejection of requests with mixed-case schemes such as htTp or htTps, or the bypassing of some requests such as https in unencrypted connections. With a fix in versions 1.27.0, 1.26.4, 1.25.9, 1.24.10, and 1.23.12, Envoy will now lowercase scheme values by default, and change the internal scheme checks that were case-sensitive to be case-insensitive. There are no known workarounds for this issue.

CNA Affected

[
  {
    "vendor": "envoyproxy",
    "product": "envoy",
    "versions": [
      {
        "version": ">= 1.26.0, < 1.26.4",
        "status": "affected"
      },
      {
        "version": ">= 1.25.0, < 1.25.9",
        "status": "affected"
      },
      {
        "version": ">= 1.24.0, < 1.24.10",
        "status": "affected"
      },
      {
        "version": "< 1.23.12",
        "status": "affected"
      }
    ]
  }
]