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.
References
| Link | Resource |
|---|---|
| https://github.com/HackC0der/CVE-Repos/blob/main/wasm-binaryen/Assertion_Failure_isRef_wasm_Type_getHeapType_commit_3ef8d19 | Exploit |
| https://github.com/WebAssembly/binaryen/ | Product |
| https://github.com/WebAssembly/binaryen/commit/1251efbc1ea471c1311d2726b2bbe061ff2a291c | Patch |
| https://github.com/WebAssembly/binaryen/issues/8633 | Exploit Issue Tracking Third Party Advisory |
| https://github.com/WebAssembly/binaryen/pull/8635 | Mitigation Patch |
| https://vuldb.com/submit/809552 | Third Party Advisory VDB Entry |
| https://vuldb.com/vuln/362554 | Third Party Advisory VDB Entry |
| https://vuldb.com/vuln/362554/cti | Permissions Required VDB Entry |
Configurations
History
21 May 2026, 17:59
| Type | Values Removed | Values Added |
|---|---|---|
| First Time |
Webassembly
Webassembly binaryen |
|
| References | () https://github.com/HackC0der/CVE-Repos/blob/main/wasm-binaryen/Assertion_Failure_isRef_wasm_Type_getHeapType_commit_3ef8d19 - Exploit | |
| References | () https://github.com/WebAssembly/binaryen/ - Product | |
| References | () https://github.com/WebAssembly/binaryen/commit/1251efbc1ea471c1311d2726b2bbe061ff2a291c - Patch | |
| References | () https://github.com/WebAssembly/binaryen/issues/8633 - Exploit, Issue Tracking, Third Party Advisory | |
| References | () https://github.com/WebAssembly/binaryen/pull/8635 - Mitigation, Patch | |
| References | () https://vuldb.com/submit/809552 - Third Party Advisory, VDB Entry | |
| References | () https://vuldb.com/vuln/362554 - Third Party Advisory, VDB Entry | |
| References | () https://vuldb.com/vuln/362554/cti - Permissions Required, VDB Entry | |
| CPE | cpe:2.3:a:webassembly:binaryen:*:*:*:*:*:*:*:* |
11 May 2026, 02:16
| Type | Values Removed | Values Added |
|---|---|---|
| New CVE |
Information
Published : 2026-05-11 02:16
Updated : 2026-05-21 17:59
NVD link : CVE-2026-8257
Mitre link : CVE-2026-8257
CVE.ORG link : CVE-2026-8257
JSON object : View
Products Affected
webassembly
- binaryen
CWE
CWE-617
Reachable Assertion