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CVE-2026-8257

WebAssembly Binaryen BrOn wasm-ir-builder.cpp makeBrOn assertion

Published: May 11, 2026Updated: May 21, 2026 Sources: CVE List NVDCWE-617
NVD MITRE
3.3CVSSLOW
EPSS Score
0.2%
Top 94.6%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
Patch Available

Description

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 Vector Breakdown

AV:LAC:LPR:LUI:NS:UC:NI:NA:L
Exploitability
AV:LAttack Vector
Local
AC:LAttack Complexity
Low
PR:LPrivileges Required
Low
UI:NUser Interaction
None
Scope
S:UScope
Unchanged
Impact
C:NConfidentiality
None
I:NIntegrity
None
A:LAvailability
Low
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Weaknesses

CWE-617

Affected Products

binaryenwebassembly
Library
OSS Libraries / generic-library
BinaryenWebAssembly
Library
OSS Libraries / generic-library
webassemblyoss-projectOSS Librariesaka webassembly

Attack Graph

Products CVE Techniques Tactics

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Exploitability

Official Patch Available
Workaround Available

MITRE ATT&CK

1 technique
Impact
View detailed technique mapping

References

https://github.com/HackC0der/CVE-Repos/blob/main/wasm-binaryen/Assertion_Failure_isRef_wasm_Type_getHeapType_commit_3ef8d19
github.com
https://github.com/WebAssembly/binaryen/
github.com
https://github.com/WebAssembly/binaryen/commit/1251efbc1ea471c1311d2726b2bbe061ff2a291c
github.com
and 5 more references View all →

Timeline

Published
May 11, 2026
Last Updated
May 21, 2026

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