CVE-2023-32731

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

Database specific

{
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2023/32xxx/CVE-2023-32731.json",
    "cna_assigner": "Google",
    "cwe_ids": [
        "CWE-440"
    ]
}

References

Affected packages

Git / github.com/grpc/grpc

Affected ranges

Type

GIT

Repo

https://github.com/grpc/grpc

Events

Introduced

358bfb581feeda5bf17dd3b96da1074d84a6ef8d

Fixed

0bf4a618b17a3f0ed61c22364913c7f66fc1c61a

Database specific

{
    "source": [
        "AFFECTED_FIELD",
        "CPE_RANGE"
    ],
    "extracted_events": [
        {
            "introduced": "1.53"
        },
        {
            "last_affected": "1.54"
        },
        {
            "introduced": "1.53.0"
        },
        {
            "fixed": "1.55.0"
        }
    ],
    "cpe": "cpe:2.3:a:grpc:grpc:*:*:*:*:*:*:*:*"
}

Type

GIT

Repo

https://github.com/grpc/grpc-go

Events

Introduced

357d7afc43fe0df74205b797525818fca8cd8f53

Fixed

a75fd73d616bea96cfa1853b5bcd0aa762be0b7b

Database specific

{
    "source": "CPE_RANGE",
    "extracted_events": [
        {
            "introduced": "1.53.0"
        },
        {
            "fixed": "1.55.0"
        }
    ],
    "cpe": "cpe:2.3:a:grpc:grpc:*:*:*:*:*:*:*:*"
}

Type

GIT

Repo

https://github.com/grpc/grpc-java

Events

Introduced

4ca6de0e8e52386301890b2860fb7a9a7c2c9b7c

Fixed

e48040541bb2b42e2465344faee241a24d747466

Database specific

{
    "source": "CPE_RANGE",
    "extracted_events": [
        {
            "introduced": "1.53.0"
        },
        {
            "fixed": "1.55.0"
        }
    ],
    "cpe": "cpe:2.3:a:grpc:grpc:*:*:*:*:*:*:*:*"
}

Affected versions

cmd/protoc-gen-go-grpc/v1.*

cmd/protoc-gen-go-grpc/v1.3.0

v1.*

v1.53.0-dev

Database specific

source

"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2023-32731.json"

vanir_signatures_modified

"2026-07-09T19:18:42Z"

vanir_signatures

[
    {
        "signature_type": "Line",
        "target": {
            "file": "core/src/main/java/io/grpc/internal/GrpcUtil.java"
        },
        "id": "CVE-2023-32731-beda6ddb",
        "source": "https://github.com/grpc/grpc-java/commit/e48040541bb2b42e2465344faee241a24d747466",
        "digest": {
            "threshold": 0.9,
            "line_hashes": [
                "186848686847118742776406955756771337553",
                "209791465984131615507118919125284817564",
                "29686144606437801261731858559341686526",
                "148346904065048773427365455448856051875"
            ]
        },
        "signature_version": "v1",
        "deprecated": false
    }
]