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TI-2026-07277 Aliases CVE-2026-8257GHSA-gmmj-chcc-2f2x

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

Priority MEDIUM 55CWE-617Published · Updated

Key facts

Attack vector
Local
Privileges required
Low
User interaction
None
Attack complexity
Low
Attack requirements
None
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · Low
Fix status
No fix listed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-617.

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.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00159 5th percentileScored 2026-11-07
Public exploit Yes 2 exploit referencesTagged by NVD and the CNA
Fix No fix listed No fixed version in the sources yet

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
WebAssemblyBinaryen117—No fix listedCNA
  • Binaryen VendorWebAssembly Affected 117 Fixed in — No fix listed CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:webassembly:binaryen:*:*:*:*:*:*:*:*up to 117VulnerableWebAssembly
  • cpe:2.3:a:webassembly:binaryen:*:*:*:*:*:*:*:* Versions up to 117 Vulnerable ·WebAssembly

Remediation

No fixed version listed by the sources yet.

Vendor assessments

Red Hat

Red Hat's page for this CVE →

Not affected: 1 product
  • Red Hat

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-8257
  2. 2026-10-03 Alias added: GHSA-gmmj-chcc-2f2x

References

Exploit 2

Patch 2

Other 1

  • TI-2020-13374 Heap-buffer-overflow in /src/wasm/wasm-binary.cpp in… CVSS 3.1MEDIUM 6.5
  • TI-2020-13373 A NULL pointer dereference was discovered in SExpressionWasmBuilder::makeBlock in… CVSS 3.1MEDIUM 6.5
  • TI-2021-20472 A Denial of Service vulnerability exits in Binaryen 103 due to an assertion abort in wasm::handle_unreachable. CVSS 3.1HIGH 7.5
  • TI-2019-05428 In Binaryen 1.38.22, there is a use-after-free problem in… CVSS 3.1MEDIUM 6.5
  • TI-2019-05400 An assertion failure was discovered in wasm::WasmBinaryBuilder::getType() in… CVSS 3.1MEDIUM 6.5
  • TI-2019-11837 An issue was discovered in Binaryen 1.38.32. CVSS 3.1MEDIUM 6.5
See all 24 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences