CVE-2023-32731

Information leak in gRPC

Description

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. If leveraged, say, between a proxy and a backend, 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. We recommend upgrading beyond the commit contained in  https://github.com/grpc/grpc/pull/33005 https://github.com/grpc/grpc/pull/33005

Remediation

Solution:

  • Fixes available in these releases: - 1.52.2: https://github.com/grpc/grpc/releases/tag/v1.52.2 https://github.com/grpc/grpc/releases/tag/v1.52.2 - 1.53.1: https://github.com/grpc/grpc/releases/tag/v1.53.1 https://github.com/grpc/grpc/releases/tag/v1.53.1 - 1.54.2: https://github.com/grpc/grpc/releases/tag/v1.54.2 https://github.com/grpc/grpc/releases/tag/v1.54.2 - 1.55.0: https://github.com/grpc/grpc/releases/tag/v1.55.0 https://github.com/grpc/grpc/releases/tag/v1.55.0

Category

7.4
CVSS
Severity: High
CVSS 3.1 •
EPSS 0.05%
Affected: Google gRPC
Published at:
Updated at:

References

Link Tags
https://github.com/grpc/grpc/pull/32309 patch
https://github.com/grpc/grpc/pull/33005 patch

Frequently Asked Questions

What is the severity of CVE-2023-32731?
CVE-2023-32731 has been scored as a high severity vulnerability.
How to fix CVE-2023-32731?
To fix CVE-2023-32731: Fixes available in these releases: - 1.52.2: https://github.com/grpc/grpc/releases/tag/v1.52.2 https://github.com/grpc/grpc/releases/tag/v1.52.2 - 1.53.1: https://github.com/grpc/grpc/releases/tag/v1.53.1 https://github.com/grpc/grpc/releases/tag/v1.53.1 - 1.54.2: https://github.com/grpc/grpc/releases/tag/v1.54.2 https://github.com/grpc/grpc/releases/tag/v1.54.2 - 1.55.0: https://github.com/grpc/grpc/releases/tag/v1.55.0 https://github.com/grpc/grpc/releases/tag/v1.55.0
Is CVE-2023-32731 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2023-32731 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2023-32731?
CVE-2023-32731 affects Google gRPC.
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