{"id":"CVE-2026-115391","aliases":["RUSTSEC-2026-0268","GHSA-x84v-gj2h-g759"],"title":"Guest controlled-size host heap allocation through WASIp3 streams","summary":"Guest controlled-size host heap allocation through WASIp3 streams","severity":"medium","cvss":5.8,"cvssVector":"CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:C/C:N/I:N/A:H","vendor":"wasmtime","product":"wasmtime","ecosystem":"rust","affected":["wasmtime >= 47.0.0, < 47.0.4"],"patched":["wasmtime 47.0.4"],"published":"2026-08-20","updated":"2026-10-24","sourceUpdated":"2026-10-24T06:25:41Z","source":"OSV","sourceUrl":"https://osv.dev/vulnerability/RUSTSEC-2026-0268","references":[{"url":"https://crates.io/crates/wasmtime"},{"url":"https://rustsec.org/advisories/RUSTSEC-2026-0268.html"},{"url":"https://github.com/bytecodealliance/wasmtime/pull/14181"},{"url":"https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-x84v-gj2h-g759","label":"GitHub Security Advisory (GHSA-x84v-gj2h-g759)"},{"url":"https://www.vulncheck.com/advisories/wasmtime-46.0.0-before-46.0.3-and-47.0.0-before-47.0.4-unbounded-heap-allocation-via-wasip3-streams","label":"VulnCheck Advisory: Wasmtime 46.0.0 before 46.0.3 and 47.0.0 before 47.0.4 Unbounded Heap Allocation via WASIp3 Streams"}],"tags":["osv","rust","cve.org"],"epss":0.00172,"epssPercentile":0.06548,"cvssSource":"cna","cwe":["CWE-770"],"ingestedAt":"2026-10-22T22:00:50.406Z","slug":"CVE-2026-115391","body":"## Overview\n\nThis is an entry in the RustSec database for the Wasmtime security advisory\nlocated at\nhttps://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-x84v-gj2h-g759\nFor more information see the GitHub-hosted security advisory.\n\n## Affected packages\n\n- `wasmtime >= 47.0.0, < 47.0.4`\n\n## Remediation\n\nUpgrade to a patched release:\n\n- `wasmtime 47.0.4`","depth":"sunlit","depthScore":32,"depthScoreParts":{"impact":31.9,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}