CVE-2026-59646

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Source
https://cve.org/CVERecord?id=CVE-2026-59646
Import Source
https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-59646.json
JSON Data
https://api.osv.dev/v1/vulns/CVE-2026-59646
Downstream
Related
Published
2026-08-03T00:48:29Z
Modified
2026-09-04T14:03:36Z
Severity
  • 8.7 (High) CVSS_V4 - CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/U:Amber CVSS Calculator
Summary
DTLS handshake reassembler allocates buffer from unchecked 24-bit length
Details

In Bouncy Castle for Java before 1.85, DTLS handshake reassembler allocates buffer from unchecked 24-bit length. This issue also affects Bouncy Castle for Java LTS before 2.73.12, and Bouncy Castle for Java FIPS (BC-FJA) before bctls-fips 1.0.24 (1.0.X series), 2.0.24 (2.0.X series) and 2.1.24 (2.1.X series).

Database specific 
{
    "cna_assigner": "bcorg",
    "cwe_ids": [
        "CWE-789"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/59xxx/CVE-2026-59646.json",
    "unresolved_ranges": [
        {
            "extracted_events": [
                {
                    "introduced": "1.0.0"
                },
                {
                    "fixed": "1.0.24"
                },
                {
                    "introduced": "2.0.0"
                },
                {
                    "fixed": "2.0.24"
                },
                {
                    "introduced": "2.1.0"
                },
                {
                    "fixed": "2.1.24"
                }
            ],
            "source": "AFFECTED_FIELD"
        }
    ]
}
References

Affected packages

Git / github.com/bcgit/bc-java

Affected ranges

Type
GIT
Repo
https://github.com/bcgit/bc-java
Events
Introduced
0 Unknown introduced commit / All previous commits are affected
Fixed
57fbd3c501f7a369f64eda311d6a709fc0bcae84
Fixed
2d98721e71bbd822ffa0f84e088eea645cf679fa
Fixed
2ea38942c7917f6d7ab4de93d8a5336d021df0d9
Database specific
Show details 
{
    "cpe": "cpe:2.3:a:bouncycastle:bc-java:*:*:*:*:*:*:*:*",
    "extracted_events": [
        {
            "introduced": "0"
        },
        {
            "fixed": "1.85"
        }
    ],
    "source": [
        "CPE_RANGE",
        "REFERENCES"
    ]
}
Type
GIT
Repo
https://github.com/bcgit/bc-lts-java
Events
Introduced
468b5082f3f0971e80bf9edb7029c17b39b9ba0c
Fixed
f101b232c5d3e07ecdd504210a57e43831d6cd65
Database specific
Show details 
{
    "cpe": "cpe:2.3:a:bouncycastle:bouncy_castle_for_java_lts:*:*:*:*:*:*:*:*",
    "extracted_events": [
        {
            "introduced": "2.73.0"
        },
        {
            "fixed": "2.73.12"
        },
        {
            "introduced": "0"
        },
        {
            "last_affected": "2.73.11"
        }
    ],
    "source": [
        "AFFECTED_FIELD",
        "CPE_RANGE"
    ]
}

Affected versions

Other
r1rv73
r1rv74
r1rv75
r1rv76
r1rv77
r1rv78
r1rv80
r1rv81
r1rv82
r1rv83
r1rv84
r2rv73dot0
r2rv73dot1
r2rv73dot10
r2rv73dot11
r2rv73dot3
r2rv73dot4
r2rv73dot6
r2rv73dot8
r2rv73dot9

Database specific

source 
"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-59646.json"
vanir_signatures 
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        "deprecated": false,
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                "320851454329274172028266083780918303540"
            ],
            "threshold": 0.9
        },
        "id": "CVE-2026-59646-245cd0a6",
        "signature_type": "Line",
        "signature_version": "v1",
        "source": "https://github.com/bcgit/bc-java/commit/2d98721e71bbd822ffa0f84e088eea645cf679fa",
        "target": {
            "file": "tls/src/main/java/org/bouncycastle/tls/DTLSClientProtocol.java"
        }
    },
    {
        "deprecated": false,
        "digest": {
            "function_hash": "33382479280882791092118122648841245730",
            "length": 810
        },
        "id": "CVE-2026-59646-27f31592",
        "signature_type": "Function",
        "signature_version": "v1",
        "source": "https://github.com/bcgit/bc-java/commit/2ea38942c7917f6d7ab4de93d8a5336d021df0d9",
        "target": {
            "file": "tls/src/main/java/org/bouncycastle/tls/DTLSReliableHandshake.java",
            "function": "DTLSReliableHandshake"
        }
    },
    {
        "deprecated": false,
        "digest": {
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                "75345587035331146488599168048672958524"
            ],
            "threshold": 0.9
        },
        "id": "CVE-2026-59646-53c38ab6",
        "signature_type": "Line",
        "signature_version": "v1",
        "source": "https://github.com/bcgit/bc-java/commit/2ea38942c7917f6d7ab4de93d8a5336d021df0d9",
        "target": {
            "file": "tls/src/main/java/org/bouncycastle/tls/DTLSServerProtocol.java"
        }
    },
    {
        "deprecated": false,
        "digest": {
            "function_hash": "109789163030238600219448007906828140137",
            "length": 6873
        },
        "id": "CVE-2026-59646-578d8326",
        "signature_type": "Function",
        "signature_version": "v1",
        "source": "https://github.com/bcgit/bc-java/commit/2d98721e71bbd822ffa0f84e088eea645cf679fa",
        "target": {
            "file": "tls/src/main/java/org/bouncycastle/tls/DTLSClientProtocol.java",
            "function": "clientHandshake"
        }
    },
    {
        "deprecated": false,
        "digest": {
            "line_hashes": [
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            ],
            "threshold": 0.9
        },
        "id": "CVE-2026-59646-60509089",
        "signature_type": "Line",
        "signature_version": "v1",
        "source": "https://github.com/bcgit/bc-java/commit/2d98721e71bbd822ffa0f84e088eea645cf679fa",
        "target": {
            "file": "tls/src/main/java/org/bouncycastle/tls/TlsUtils.java"
        }
    },
    {
        "deprecated": false,
        "digest": {
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            "length": 6825
        },
        "id": "CVE-2026-59646-725bb834",
        "signature_type": "Function",
        "signature_version": "v1",
        "source": "https://github.com/bcgit/bc-java/commit/2ea38942c7917f6d7ab4de93d8a5336d021df0d9",
        "target": {
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            "function": "clientHandshake"
        }
    },
    {
        "deprecated": false,
        "digest": {
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            "length": 503
        },
        "id": "CVE-2026-59646-7486b81a",
        "signature_type": "Function",
        "signature_version": "v1",
        "source": "https://github.com/bcgit/bc-java/commit/2d98721e71bbd822ffa0f84e088eea645cf679fa",
        "target": {
            "file": "tls/src/main/java/org/bouncycastle/tls/TlsProtocol.java",
            "function": "beginHandshake"
        }
    },
    {
        "deprecated": false,
        "digest": {
            "function_hash": "276753422750615690193765852091165592276",
            "length": 1422
        },
        "id": "CVE-2026-59646-7ff48b00",
        "signature_type": "Function",
        "signature_version": "v1",
        "source": "https://github.com/bcgit/bc-java/commit/2ea38942c7917f6d7ab4de93d8a5336d021df0d9",
        "target": {
            "file": "tls/src/main/java/org/bouncycastle/tls/DTLSReliableHandshake.java",
            "function": "processRecord"
        }
    },
    {
        "deprecated": false,
        "digest": {
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            ],
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        },
        "id": "CVE-2026-59646-acf5e8d8",
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        "source": "https://github.com/bcgit/bc-java/commit/2d98721e71bbd822ffa0f84e088eea645cf679fa",
        "target": {
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        }
    },
    {
        "deprecated": false,
        "digest": {
            "function_hash": "288526351441152287905145328246354800467",
            "length": 6565
        },
        "id": "CVE-2026-59646-bacec00c",
        "signature_type": "Function",
        "signature_version": "v1",
        "source": "https://github.com/bcgit/bc-java/commit/2ea38942c7917f6d7ab4de93d8a5336d021df0d9",
        "target": {
            "file": "tls/src/main/java/org/bouncycastle/tls/DTLSServerProtocol.java",
            "function": "serverHandshake"
        }
    },
    {
        "deprecated": false,
        "digest": {
            "line_hashes": [
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        },
        "id": "CVE-2026-59646-bee5cf64",
        "signature_type": "Line",
        "signature_version": "v1",
        "source": "https://github.com/bcgit/bc-java/commit/2ea38942c7917f6d7ab4de93d8a5336d021df0d9",
        "target": {
            "file": "tls/src/main/java/org/bouncycastle/tls/DTLSClientProtocol.java"
        }
    },
    {
        "deprecated": false,
        "digest": {
            "function_hash": "315101957165243595735170460633247883062",
            "length": 6613
        },
        "id": "CVE-2026-59646-e5f855d0",
        "signature_type": "Function",
        "signature_version": "v1",
        "source": "https://github.com/bcgit/bc-java/commit/2d98721e71bbd822ffa0f84e088eea645cf679fa",
        "target": {
            "file": "tls/src/main/java/org/bouncycastle/tls/DTLSServerProtocol.java",
            "function": "serverHandshake"
        }
    },
    {
        "deprecated": false,
        "digest": {
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            "threshold": 0.9
        },
        "id": "CVE-2026-59646-ed53b872",
        "signature_type": "Line",
        "signature_version": "v1",
        "source": "https://github.com/bcgit/bc-java/commit/2d98721e71bbd822ffa0f84e088eea645cf679fa",
        "target": {
            "file": "tls/src/main/java/org/bouncycastle/tls/TlsProtocol.java"
        }
    },
    {
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        "digest": {
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        "target": {
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        }
    }
]
vanir_signatures_modified 
"2026-09-04T14:03:36Z"