CVE-2023-26489 — wasmtime is a fast and secure runtime for WebAssembly

wasmtime is a fast and secure runtime for WebAssembly. In affected versions wasmtime's code generator, Cranelift, has a bug on x86_64 targets where address-mode computation mistakenly would calculate a 35-bit effective address instead of WebAssembly's defined 33-bit eff

01What is this vulnerability?

wasmtime is a fast and secure runtime for WebAssembly. In affected versions wasmtime's code generator, Cranelift, has a bug on x86_64 targets where address-mode computation mistakenly would calculate a 35-bit effective address instead of WebAssembly's defined 33-bit effective address. This bug means that, with default codegen settings, a wasm-controlled load/store operation could read/write…

02Affected products

Vendor	Product	Versions
bytecodealliance	wasmtime	cranelift-codegen: >= 0.84.0, < 0.91.1, cranelift-codegen: >= 0.92.0, < 0.92.1, cranelift-codegen: >= 0.93.0, < 0.93.1, wasmtime: >= 0.37.0, < 4.0.1, wasmtime: >= 5.0.0, < 5.0.1, wasmtime: >= 6.0.0, < 6.0.1

03Active exploitation status

Not currently listed on the CISA Known Exploited Vulnerabilities (KEV) catalog. EPSS is the best forward-looking signal — see the EPSS row above.

04Recommended remediation

• Patch to a fixed version listed in the vendor advisory (see references below).
• Mitigate with WAF rules, network egress filters, or feature flags where the patch is not yet available.
• Hunt historical logs for exploitation indicators — see Detection signatures below.

05Technical details

For the full vendor write-up, exploit chains, and reference implementations, see the references list in section 09.

06Detection signatures

Ask SARA in chat to draft a starting detection for this CVE in your stack of choice.

07Related CVEs

No directly-cited follow-up CVEs in the KB record for this advisory. The references list in section 09 carries the vendor cross-references.

08Timeline

• Published: 2023-03-08T19:59:57.419Z
• Last modified: 2025-02-25T14:59:40.063Z

09References

• github.com — https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-ff4p-7xrq-…
• github.com — https://github.com/bytecodealliance/wasmtime/commit/63fb30e4b4415455d47b3da5a19d…
• docs.rs — https://docs.rs/wasmtime/latest/wasmtime/struct.Config.html#method.static_memory…
• docs.rs — https://docs.rs/wasmtime/latest/wasmtime/struct.Config.html#method.static_memory…
• groups.google.com — https://groups.google.com/a/bytecodealliance.org/g/sec-announce/c/Mov-ItrNJsQ