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CVE-2023-35944 (GCVE-0-2023-35944)

Vulnerability from cvelistv5 – Published: 2023-07-25 18:35 – Updated: 2024-10-23 20:18
VLAI
Title
Envoy vulnerable to incorrect handling of HTTP requests and responses with mixed case schemes
Summary
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.
Severity
8.2 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:N
SSVC
Exploitation: poc Automatable: no Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2024-10-23 20:18 UTC
CWE
  • CWE-20 - Improper Input Validation
Assigner
References
Impacted products
Vendor Product Version CPE status
envoyproxy envoy Affected: >= 1.26.0, < 1.26.4
Affected: >= 1.25.0, < 1.25.9
Affected: >= 1.24.0, < 1.24.10
Affected: < 1.23.12
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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
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  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


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