Use After Free in Bytecodealliance Wasmtime
CVE-2021-39216
Wasmtime is an open source runtime for WebAssembly & WASI. In Wasmtime from version 0.19.0 and before version 0.30.0 there was a use-after-free bug when passing `externref`s from the host to guest Wasm content. To trigger the bug, you have…
Vulnerability class: Use-After-Free
EPSS: 0.002 (35.7th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 6.3 (Medium). Vector: CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:H/A:H.
Affected products
- Bytecodealliance Wasmtime — versions >=0.19.0, <=0.29.0
Weakness classification (CWE)
Public proof-of-concept exploits
References
- github.com/bytecodealliance/wasmtime/security/advisories/GHSA-v4cp-h94r-m7xf (x_refsource_CONFIRM)
- github.com/bytecodealliance/wasmtime/commit/101998733b74624cbd348a2366d05760b40… (x_refsource_MISC)
- crates.io/crates/wasmtime (x_refsource_MISC)
- FEDORA-2021-68713440cb (vendor-advisory, x_refsource_FEDORA)
- FEDORA-2021-1805eacb48 (vendor-advisory, x_refsource_FEDORA)
Frequently asked questions
- What is CVE-2021-39216?
- CVE-2021-39216 is a medium-severity vulnerability in Bytecodealliance Wasmtime, classified under Use After Free. CVSS score: 6.3/10. Published 2021-09-17.
- How severe is CVE-2021-39216?
- Medium severity. CVSS v3 base score is 6.3 out of 10.
- Is CVE-2021-39216 known to be exploited?
- 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.