Resource exhaustion in Bytecodealliance Wasmtime
CVE-2026-115380
Wasmtime before 36.0.17, 37.0.0 before 48.0.4, and 49.0.0 before 49.0.2 contains a denial of service vulnerability in the wasmtime-wasi WASI preview 0 poll_oneoff adapter, which performs O(n) host work per subscription without consuming or checking fuel. Malicious guest modules can pass many subscriptions to force long-running host computation that ignores configured fuel limits.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 4.0 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L.
EPSS exploit prediction
No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.
Affected products
Weakness classification (CWE)
References
- github.com/bytecodealliance/wasmtime/security/advisories/GHSA-j366-h8gg-77pm (vendor-advisory)
- www.vulncheck.com/advisories/wasmtime-before-36.0.17-37.0.0-before-48.0.4-and-4… (third-party-advisory)
Frequently asked questions
- What is CVE-2026-115380?
- CVE-2026-115380 is a medium-severity vulnerability in Bytecodealliance Wasmtime, classified under Allocation of Resources Without Limits or Throttling. CVSS score: 4.0/10. Published 2026-10-22.
- How severe is CVE-2026-115380?
- Medium severity. CVSS v3 base score is 4.0 out of 10.