CVE-2026-8257

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.

CVSS v3 3.3 LOW
CVSS v2.0 1.7 LOW

3.3^/10

CVSS v3 : LOW

Vector :

Exploitability : 1.8 / Impact : 1.4

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact LOW

Scope UNCHANGED

1.7^/10

CVSS v2.0 : LOW

Vector : AV:L/AC:L/Au:S/C:N/I:N/A:P

Exploitability : 3.1 / Impact : 2.9

Access Vector LOCAL

Access Complexity LOW

Authentication SINGLE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact PARTIAL

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

Configuration 1 (hide)

cpe:2.3:a:webassembly:binaryen:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-05-11 02:16

Updated : 2026-07-23 20:10

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

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