CVE-2026-54912: bytecodealliance wasm-micro-runtime · Out-of-bounds Write
Affects bytecodealliance wasm-micro-runtimeSource CVE Database V5
Not known to be exploited · CVSS 8.8 High : upgrade to 2.4.5 soon.
Data as of 5 Nov 2026, 17:34 UTC
Thin evidence
One scorer or none| CNA (GitHub_M) | CVSS 4.0 | 8.8 |
|---|
- Patch
- Available – fixed in 2.4.5
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:H/VA:H/SC:N/SI:N/SA:NExploitation evidence
Disclosed: evidence found.
CVE published 5 Nov 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 5 Nov 2026.
What to do
Upgrade bytecodealliance wasm-micro-runtime to 2.4.5.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| bytecodealliancewasm-micro-runtime | Affected
| Fixed in
|
Description
WebAssembly Micro Runtime (WAMR) is a lightweight standalone WebAssembly (Wasm) runtime. Prior to 2.4.5, the two-pass fast interpreter loader in core/iwasm/interpreter/wasm_loader.c can make inconsistent constant-table decisions between the sizing pass and the emitting pass. After duplicate constants inflate the first pass beyond the constant-slot limit, wasm_loader_get_const_offset emits later constants inline, but the between-pass sort and deduplication reduces the table so the second pass can choose table references and cause reserve_block_ret to emit additional copy operands that were not included in code_compiled_peak_size. A crafted module can therefore make the second pass write partially attacker-controlled compiled-code data beyond the heap buffer allocated from the first pass's size calculation during wasm_runtime_load, before guest code executes. This can corrupt host heap metadata and deterministically crash the process, causing denial of service; further consequences depend on the host application's heap layout. Builds using WAMR_BUILD_FAST_INTERP=1 are affected; disabling the fast interpreter avoids the vulnerable loader. This issue is fixed in version 2.4.5.
References
- github.com/wasm-micro-runtime/wasm-micro-runtime/security/advisories/GHSA-jjv3-x3jf-cg49 (opens in a new tab)
- github.com/wasm-micro-runtime/wasm-micro-runtime/commit/b1353b5e8983047ff68829c99abf1355d5f389cf (opens in a new tab)
- gist.github.com/shumbo/b710c35b005ed871447fce385d1ab760 (opens in a new tab)
- github.com/wasm-micro-runtime/wasm-micro-runtime/releases/tag/WAMR-2.4.5 (opens in a new tab)