High severity · published Jul 25, 2023
CVE-2023-35943
Envoy is an open source edge and service proxy designed for cloud-native applications
7.5
CVSS
0.7%
EPSS
No
On KEV
Description
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.7% · higher than 51% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
EN
Envoy · Envoyproxy
1.23.0 before 1.23.12; 1.24.0 before 1.24.10; 1.25.0 before 1.25.9; 1.26.0 before 1.26.4 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2023-35943
CVE.org
https://www.cve.org/CVERecord?id=CVE-2023-35943
Exploit
https://github.com/envoyproxy/envoy/security/advisories/GHSA-mc6h-6j9x-v3gq
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