// For flags

CVE-2023-35943

Envoy vulnerable to CORS filter segfault when origin header is removed

Severity Score

7.5
*CVSS v3.1

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

1
*Multiple Sources

Exploited in Wild

-
*KEV

Decision

-
*SSVC
Descriptions

Envoy is an open source edge and service proxy designed for cloud-native applications. Prior to versions 1.27.0, 1.26.4, 1.25.9, 1.24.10, and 1.23.12, the CORS filter will segfault and crash Envoy when the `origin` header is removed and deleted between `decodeHeaders`and `encodeHeaders`. Versions 1.27.0, 1.26.4, 1.25.9, 1.24.10, and 1.23.12 have a fix for this issue. As a workaround, do not remove the `origin` header in the Envoy configuration.

A flaw was found in Envoy. Suppose an origin header is configured to be removed with request_headers_to_remove: origin. The CORS filter will segfault and crash Envoy when the origin header is removed and deleted between decodeHeaders and encodeHeaders.

*Credits: N/A
CVSS Scores
Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High
Attack Vector
Network
Attack Complexity
Low
Privileges Required
Low
User Interaction
Required
Scope
Unchanged
Confidentiality
Low
Integrity
None
Availability
High
* Common Vulnerability Scoring System
SSVC
  • Decision:-
Exploitation
-
Automatable
-
Tech. Impact
-
* Organization's Worst-case Scenario
Timeline
  • 2023-06-20 CVE Reserved
  • 2023-07-25 CVE Published
  • 2024-07-31 EPSS Updated
  • 2024-08-02 CVE Updated
  • 2024-08-02 First Exploit
  • ---------- Exploited in Wild
  • ---------- KEV Due Date
CWE
  • CWE-416: Use After Free
CAPEC
Affected Vendors, Products, and Versions
Vendor Product Version Other Status
Vendor Product Version Other Status <-- --> Vendor Product Version Other Status
Envoyproxy
Search vendor "Envoyproxy"
Envoy
Search vendor "Envoyproxy" for product "Envoy"
>= 1.23.0 < 1.23.12
Search vendor "Envoyproxy" for product "Envoy" and version " >= 1.23.0 < 1.23.12"
-
Affected
Envoyproxy
Search vendor "Envoyproxy"
Envoy
Search vendor "Envoyproxy" for product "Envoy"
>= 1.24.0 < 1.24.10
Search vendor "Envoyproxy" for product "Envoy" and version " >= 1.24.0 < 1.24.10"
-
Affected
Envoyproxy
Search vendor "Envoyproxy"
Envoy
Search vendor "Envoyproxy" for product "Envoy"
>= 1.25.0 < 1.25.9
Search vendor "Envoyproxy" for product "Envoy" and version " >= 1.25.0 < 1.25.9"
-
Affected
Envoyproxy
Search vendor "Envoyproxy"
Envoy
Search vendor "Envoyproxy" for product "Envoy"
>= 1.26.0 < 1.26.4
Search vendor "Envoyproxy" for product "Envoy" and version " >= 1.26.0 < 1.26.4"
-
Affected