CVE-2023-32731

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

CVSS Metrics

• v3.1•HIGH•Score: 7.4CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:H
• v3.1•HIGH•Score: 7.5CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

EPSS Trends

Current EPSS score: 0.07%• Percentile: 23%

Techniques & Countermeasures

• CWE-440•Expected Behavior Violation

  A feature, API, or function does not perform according to its specification.

Affected Systems

• RubyGems•grpc

  ≥ 1.53.0, < 1.53.1 | ≥ 1.54.0, < 1.54.2

• google•grpc

  ≥ 1.53, ≤ 1.54

• grpc•grpc

  ≥ 1.53.0, < 1.55.0

• io.grpc•grpc-protobuf

  ≥ 1.53.0, < 1.53.1 | ≥ 1.54.0, < 1.54.2

• PyPI•grpcio

  ≥ 1.53.0, < 1.53.1 | ≥ 1.54.0, < 1.54.2

References (9)

• https://github.com/grpc/grpc/pull/32309
• https://github.com/grpc/grpc/pull/33005
• https://nvd.nist.gov/vuln/detail/CVE-2023-32731
• https://github.com/grpc/grpc/issues/33463
• https://github.com/grpc/grpc/commit/29d8beee0ac2555773b2a2dda5601c74a95d6c10
• https://github.com/grpc/grpc/commit/65a2a895afaf1d2072447b9baf246374b182a946
• https://github.com/grpc/grpc/releases/tag/v1.53.1
• https://github.com/grpc/grpc/releases/tag/v1.54.2
• https://github.com/rubysec/ruby-advisory-db/blob/master/gems/grpc/CVE-2023-32731.yml