CVE-2026-12852

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Source
https://cve.org/CVERecord?id=CVE-2026-12852
Import Source
https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2026-12852.json
JSON Data
https://api.test.osv.dev/v1/vulns/CVE-2026-12852
Downstream
DEBIAN (1)
openSUSE (2)
SUSE (3)
UBUNTU (1)
Related
openSUSE (2)
SUSE (3)
Published
2026-08-03T02:55:02Z
Modified
2026-10-16T10:11:29Z
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
MLS wire decoder allocates attacker-declared opaque length before bounds check
Details

In Bouncy Castle for Java before 1.85, MLS wire decoder allocates attacker-declared opaque length before bounds check.

Database specific 
{
    "cna_assigner": "bcorg",
    "cwe_ids": [
        "CWE-789"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/12xxx/CVE-2026-12852.json"
}
References

Affected packages

Git / github.com/bcgit/bc-java

Affected ranges

Type
GIT
Repo
https://github.com/bcgit/bc-java
Events
Introduced
9032821b326fba9fec7528899dfffa79f9f19aef
Fixed
57fbd3c501f7a369f64eda311d6a709fc0bcae84
Fixed
a747038bb5bbd5e29fb2b7607ab38af1fd8d1790
Database specific
Show details 
{
    "extracted_events": [
        {
            "range": [
                {
                    "introduced": "1.73"
                },
                {
                    "fixed": "1.85"
                }
            ],
            "source": "AFFECTED_FIELD",
            "strategy": "StandardRange"
        },
        {
            "range": [
                {
                    "fixed": "a747038bb5bbd5e29fb2b7607ab38af1fd8d1790"
                }
            ],
            "source": "REFERENCES_COMMIT"
        }
    ]
}

Affected versions

Other
r1rv73
r1rv74
r1rv75
r1rv76
r1rv77
r1rv78
r1rv80
r1rv81
r1rv82
r1rv83
r1rv84

Database specific

source 
"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2026-12852.json"
vanir_signatures 
[
    {
        "deprecated": false,
        "digest": {
            "function_hash": "92295335491211025736448040308708710108",
            "length": 266
        },
        "id": "CVE-2026-12852-8ef8f8a8",
        "signature_type": "Function",
        "signature_version": "v1",
        "source": "https://github.com/bcgit/bc-java/commit/a747038bb5bbd5e29fb2b7607ab38af1fd8d1790",
        "target": {
            "file": "mls/src/main/java/org/bouncycastle/mls/codec/MLSInputStream.java",
            "function": "readAll"
        }
    },
    {
        "deprecated": false,
        "digest": {
            "line_hashes": [
                "165593616814765860092658684244893193843",
                "235063781483236034420533035909420169182",
                "338363851271881968021307034365317425750",
                "57069292492115989365116917505383793201"
            ],
            "threshold": 0.9
        },
        "id": "CVE-2026-12852-94684acf",
        "signature_type": "Line",
        "signature_version": "v1",
        "source": "https://github.com/bcgit/bc-java/commit/a747038bb5bbd5e29fb2b7607ab38af1fd8d1790",
        "target": {
            "file": "mls/src/main/java/org/bouncycastle/mls/codec/MLSInputStream.java"
        }
    },
    {
        "deprecated": false,
        "digest": {
            "function_hash": "235437277780272800208970287964717024610",
            "length": 192
        },
        "id": "CVE-2026-12852-96102330",
        "signature_type": "Function",
        "signature_version": "v1",
        "source": "https://github.com/bcgit/bc-java/commit/a747038bb5bbd5e29fb2b7607ab38af1fd8d1790",
        "target": {
            "file": "mls/src/test/java/org/bouncycastle/mls/test/AllTests.java",
            "function": "suite"
        }
    },
    {
        "deprecated": false,
        "digest": {
            "line_hashes": [
                "218902235986088413190436015791436355394",
                "142954904135386976371266999333847028157",
                "25430774948821357363219746391799485253",
                "296670093081609531050956418526677471737"
            ],
            "threshold": 0.9
        },
        "id": "CVE-2026-12852-a25814bb",
        "signature_type": "Line",
        "signature_version": "v1",
        "source": "https://github.com/bcgit/bc-java/commit/a747038bb5bbd5e29fb2b7607ab38af1fd8d1790",
        "target": {
            "file": "mls/src/test/java/org/bouncycastle/mls/test/AllTests.java"
        }
    }
]
vanir_signatures_modified 
"2026-10-16T10:11:29Z"