#VU78679 Input validation error in envoy - CVE-2023-35944

Vulnerability identifier: #VU78679

Vulnerability risk: High

CVSSv4.0: 7.8 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N/E:P/U:Amber]

CVE-ID: CVE-2023-35944

CWE-ID: CWE-20

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
envoy
Server applications / IDS/IPS systems, Firewalls and proxy servers

Vendor: Cloud Native Computing Foundation

Description

The vulnerability allows a remote attacker to compromise the target system.

The vulnerability exists due to incorrect handling of requests and responses with mixed case schemes. A remote attacker can pass specially crafted input to the application and bypass some requests with mixed schemes.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

envoy: 1.23.0 - 1.26.3

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External links
https://github.com/envoyproxy/envoy/security/advisories/GHSA-pvgm-7jpg-pw5g

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability. However, proof of concept for this vulnerability is available.