Vulnerability · CVE-2026-8257
A vulnerability was detected in WebAssembly Binaryen up to 117.
Published May 11, 2026 · catalog updated Jul 23, 2026 · A vulnerability was detected
Check if you run it
No confirmed exploitation is on record for CVE-2026-8257. EPSS is 0.19%. Act only if a listed version of A vulnerability was detected is installed.
Gaps on this record
- The stored product name is a package slug. The name on this page is taken from the title (A vulnerability was detected).
- No version range is stored. A customer cannot check an installed version against this record.
- No vendor fix or required action is stored. Compare the linked advisory before you change production.
- Severity
- Low1.9
- Known exploitation
- Not in CISA/VulnCheck KEV
- EPSS
- 0.19%
- Remediation
- Advisory link
- Affected products
- cpe webassembly/binaryen
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.
Are you affected?
Enter the version you run. The result uses only the ranges stored on this record.
The check returns affected, not affected, or incomplete. It does not guess a version that is missing from the record.
- cpe webassembly/binaryenversion unspecified
How to fix CVE-2026-8257
Recommended remediation
A patch or advisory reference is linked. Open the original publisher for availability by product version.
Official advisories
What to do
Three questions, each answered from this record only. Confirm the vendor advisory before you patch.
Should you patch?
No confirmed exploitation is on record for CVE-2026-8257. EPSS is 0.19%. Act only if a listed version of A vulnerability was detected is installed.
Which versions are affected?
Affected version ranges are not on this record. Compare the installed version with the linked vendor advisory before you change production.
What should an analyst verify?
CWE-617. EPSS 0.19%. There is no CISA KEV listing. No Exploit-DB or Metasploit reference is linked. Use the source links for the original advisory.
Code
The project this record applies to. Exploit listings stay in References.
Timeline
Detection, updates, and resolution for this record.
May 11, 2026 · NIST NVD
Detected
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 su
Jul 23, 2026 · NIST NVD
Updated
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 su
Sources
- CVE.orgVulnerability recordCVE-2026-8257
Official CVE identifier
cve.org - FIRST EPSSExploitation probabilityCVE-2026-8257
30-day exploitation probability 0.2%
first.org - NIST NVDVulnerability recordCVE-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 l
nvd.nist.gov
References
Freshness
Last verified in this catalog Oct 18, 2026. Significant claims (KEV, EPSS, CVSS, affected ranges) come from the source rows above — open the original publisher for the authoritative advisory.