CVE-2026-8257

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Source
https://cve.org/CVERecord?id=CVE-2026-8257
Import Source
https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-8257.json
JSON Data
https://api.osv.dev/v1/vulns/CVE-2026-8257
Downstream
Related
Published
2026-05-11T00:30:13Z
Modified
2026-10-28T11:18:41Z
Severity
  • 1.9 (Low) CVSS_V4 - CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P CVSS Calculator
Summary
WebAssembly Binaryen BrOn wasm-ir-builder.cpp makeBrOn assertion
Details

A vulnerability was detected in WebAssembly Binaryen up to 117. This issue affects the function IRBuilder::makeBrOn of the file src/wasm/wasm-ir-builder.cpp of the component BrOn Parser. Performing a manipulation results in reachable assertion. The attack needs to be approached locally. The exploit is now public and may be used. The patch is named 1251efbc1ea471c1311d2726b2bbe061ff2a291c. It is suggested to install a patch to address this issue.

Database specific 
{
    "cna_assigner": "VulDB",
    "cwe_ids": [
        "CWE-617"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/8xxx/CVE-2026-8257.json"
}
References

Affected packages

Git / github.com/webassembly/binaryen

Affected ranges

Type
GIT
Repo
https://github.com/webassembly/binaryen
Events
Introduced
c62a0c97168e88f97bca4bd96298a5ffc041844d
Fixed
1251efbc1ea471c1311d2726b2bbe061ff2a291c
Database specific
Show details 
{
    "extracted_events": [
        {
            "range": [
                {
                    "introduced": "117"
                },
                {
                    "last_affected": "117"
                }
            ],
            "source": "AFFECTED_FIELD",
            "strategy": "StandaloneSingleVersion"
        },
        {
            "range": [
                {
                    "fixed": "1251efbc1ea471c1311d2726b2bbe061ff2a291c"
                }
            ],
            "source": "REFERENCES_COMMIT"
        }
    ]
}

Affected versions

Other
117
rebuild-121
version_117
version_118
version_119
version_120
version_120_b
version_121
version_122
version_123
version_124
version_125
version_126
version_127
version_128
version_129

Database specific

source 
"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-8257.json"
vanir_signatures 
[
    {
        "deprecated": false,
        "digest": {
            "line_hashes": [
                "120838197908276583638706545592244564526",
                "199647166938005591249838151950569417417",
                "12001628279394536810634066111217821325"
            ],
            "threshold": 0.9
        },
        "id": "CVE-2026-8257-0730faa9",
        "signature_type": "Line",
        "signature_version": "v1",
        "source": "https://github.com/webassembly/binaryen/commit/1251efbc1ea471c1311d2726b2bbe061ff2a291c",
        "target": {
            "file": "src/wasm/wasm-ir-builder.cpp"
        }
    },
    {
        "deprecated": false,
        "digest": {
            "function_hash": "336226870441999808140469905206245226879",
            "length": 2948
        },
        "id": "CVE-2026-8257-bf5414a1",
        "signature_type": "Function",
        "signature_version": "v1",
        "source": "https://github.com/webassembly/binaryen/commit/1251efbc1ea471c1311d2726b2bbe061ff2a291c",
        "target": {
            "file": "src/wasm/wasm-ir-builder.cpp",
            "function": "IRBuilder::makeBrOn"
        }
    }
]
vanir_signatures_modified 
"2026-10-28T11:18:41Z"