#VU79797 Input validation error in gRPC - CVE-2023-32731
Published: August 21, 2023
Vulnerability identifier: #VU79797
Vulnerability risk: Medium
CVSSv4.0: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N/E:U/U:Green
CVE-ID: CVE-2023-32731
CWE-ID: CWE-20
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerable software:
gRPC
gRPC
Software vendor:
grpc
grpc
Description
The vulnerability allows a remote attacker to gain access to sensitive information.
The vulnerability exists due to insufficient validation of user-supplied input when parsing HTTP2 requests. When gRPC HTTP2 stack raised a header size exceeded error, it skipped parsing the rest of the HPACK frame. This caused any HPACK table mutations to also be skipped, resulting in a desynchronization of HPACK tables between sender and receiver. This could lead to requests from the proxy being interpreted as containing headers from different proxy clients, leading to an information leak that can be used for privilege escalation or data exfiltration.
Remediation
Install updates from vendor's website.