CVE-2026-8257
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.
Predictions
Heuristic predictions, AS-IS, for prioritization only.
Mitigations
No mitigations published for this CVE yet.
The vendor-content worker queues fetches as references arrive (check back in a few minutes). Or โ if you've already worked around this in production โ publish your fix to the community-verified tier.
โ Propose a mitigation on Community โ Mitigations published via the community go through AI scoring + 2 human reviewers + 7-day silent objection window before landing here withsource_tier=community-verified.
OS impact
| OS | Version | Status | Fixed in |
|---|---|---|---|
| debian | bookworm | affected | |
| debian | bullseye | affected | |
| debian | forky | affected | |
| debian | sid | affected | |
| debian | trixie | affected | |
Application impact
| Vendor | Product | Versions | Fixed |
|---|---|---|---|
| webassembly | binaryen | {"endIncluding":"117"} | |
References
- https://github.com/HackC0der/CVE-Repos/blob/main/wasm-binaryen/Assertion_Failure_isRef_wasm_Type_getHeapType_commit_3ef8d19
- https://github.com/WebAssembly/binaryen/
- https://github.com/WebAssembly/binaryen/commit/1251efbc1ea471c1311d2726b2bbe061ff2a291c
- https://github.com/WebAssembly/binaryen/issues/8633
- https://github.com/WebAssembly/binaryen/pull/8635
- https://vuldb.com/submit/809552
- https://vuldb.com/vuln/362554
- https://vuldb.com/vuln/362554/cti
- https://security-tracker.debian.org/tracker/CVE-2026-8257
CWEs
CWE-617
Community-verified mitigations for this CVE will appear above when contributors publish them.
Verify integrity in audit chain (admin only). AS-IS.