Critical severity · published Apr 4, 2023
CVE-2023-27491
Envoy is an open source edge and service proxy designed for cloud-native applications
9.1
CVSS
0.9%
EPSS
No
On KEV
Description
Envoy is an open source edge and service proxy designed for cloud-native applications. Compliant HTTP/1 service should reject malformed request lines. Prior to versions 1.26.0, 1.25.3, 1.24.4, 1.23.6, and 1.22.9, There is a possibility that non compliant HTTP/1 service may allow malformed requests, potentially leading to a bypass of security policies. This issue is fixed in versions 1.26.0, 1.25.3, 1.24.4, 1.23.6, and 1.22.9.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.9% · higher than 59% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
EN
Envoy · Envoyproxy
before 1.22.9; 1.23.0 before 1.23.6; 1.24.0 before 1.24.4; 1.25.0 before 1.25.3 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2023-27491
CVE.org
https://www.cve.org/CVERecord?id=CVE-2023-27491
Not Applicable
https://datatracker.ietf.org/doc/html/rfc9113#section-8.3
Not Applicable
https://datatracker.ietf.org/doc/html/rfc9114#section-4.3.1
Exploit
https://github.com/envoyproxy/envoy/security/advisories/GHSA-5jmv-cw9p-f9rp
Not Applicable
https://www.rfc-editor.org/rfc/rfc9110#section-5.6.2
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