Medium
binaryen — security advisory
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.
- Products
- binaryen
- Affected versions
- 105-1, 108-1, 120-3, 120-4, 120-4build1, 130-2, 130-3, 131-2, 89-1, 90-1, 91-1, 99-3
- Fixed versions
- Not specified
- CVEs
- CVE-2026-8257
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 31 Oct 2026, 03:20 UTC · Revision 1
Source evidence
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.
osv:UBUNTU-CVE-2026-8257
binaryen
Fixed versions: Not specified
binaryen
Fixed versions: Not specified
binaryen
Fixed versions: Not specified
binaryen
Fixed versions: Not specified
binaryen
Fixed versions: Not specified
binaryen
Fixed versions: Not specified
Complete source record
{
"id": "bbbd628997db5b54ea78a423a6861c2bde9fdc2b586cf519589d8185afd985ba",
"url": "https://osv.dev/vulnerability/UBUNTU-CVE-2026-8257",
"method": "structured",
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"title": "UBUNTU-CVE-2026-8257",
"summary": "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.",
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},
{
"type": "Ubuntu",
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"database_specific": {
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],
"modified": "2026-10-17T13:01:11.350906572Z",
"provider": "osv",
"upstream": [
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],
"references": [
"https://ubuntu.com/security/CVE-2026-8257",
"https://www.cve.org/CVERecord?id=CVE-2026-8257"
]
},
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"evidence": "/upstream"
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],
"security_relevant": true,
"severity_evidence": "/severity/1/score"
},
"source_id": "core-osv",
"document_id": 361177,
"published_at": "2026-05-11T02:16:00+00:00"
}