{"id":"CVE-2026-115386","aliases":["DEBIAN-CVE-2026-115386","EUVD-2026-108314","GHSA-7vfm-vg2r-wpmh","GHSA-96f6-r43r-8c24","RUSTSEC-2026-0323","UBUNTU-CVE-2026-115386"],"status":"published","title":"Wasmtime before 36.0.17, 37.0.0 before 48.0.4, and 49.0.0 before 49.0.2 Memory Disclosure via fd_readdir","description":"Wasmtime before 36.0.17, 37.0.0 before 48.0.4, and 49.0.0 before 49.0.2 contains an information disclosure vulnerability in the WASIp1 fd_readdir implementation that copies uninitialized struct padding into guest memory. Guests with a preopened directory can list entries to receive three bytes of leftover host stack or heap memory per directory entry.","severity":{"version":"4.0","score":2.1,"vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:P/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N","level":"low","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-12","score":0.00197,"percentile":0.09578,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-908"],"published":"2026-10-02T12:00:00Z","modified":"2026-11-02T22:00:07Z","fixes":[{"ecosystem":"Debian:14","package":"rust-wasmtime","fixed_in":["36.0.20+dfsg-1"],"sources":["osv"]},{"ecosystem":"crates.io","package":"wasmtime-wasi","fixed_in":["36.0.17","48.0.4","49.0.2"],"sources":["osv"]}],"affected":[{"source":"osv","ecosystem":"Debian:13","package":"rust-wasmtime","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["26.0.1+dfsg-10","26.0.1+dfsg-3","26.0.1+dfsg-4","26.0.1+dfsg-5","26.0.1+dfsg-6","26.0.1+dfsg-7","26.0.1+dfsg-8","26.0.1+dfsg-9","27.0.0+dfsg-2","27.0.0+dfsg-3","27.0.0+dfsg-4","28.0.1+dfsg-1","28.0.1+dfsg-2","28.0.1+dfsg-3","29.0.1+dfsg-1","29.0.1+dfsg-2","29.0.1+dfsg-3","29.0.1+dfsg-4","29.0.1+dfsg-5","29.0.1+dfsg-6","29.0.1+dfsg-7","29.0.1+dfsg-8","36.0.11+dfsg-1","36.0.12+dfsg-1","36.0.12+dfsg-2","36.0.12+dfsg-3","36.0.13+dfsg-1","36.0.20+dfsg-1","36.0.5+dfsg-1","36.0.5+dfsg-2","36.0.5+dfsg-3","36.0.5+dfsg-4","36.0.5+dfsg-5","36.0.6+dfsg-1","36.0.6+dfsg-2","36.0.6+dfsg-3","36.0.6+dfsg-4","36.0.6+dfsg-5","36.0.6+dfsg-6","36.0.6+dfsg-7","36.0.7+dfsg-1","36.0.8+dfsg-1","36.0.9+dfsg-1","36.0.9+dfsg-2"]},{"source":"osv","ecosystem":"Debian:14","package":"rust-wasmtime","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"36.0.20+dfsg-1"}]}],"versions":["26.0.1+dfsg-10","26.0.1+dfsg-3","26.0.1+dfsg-4","26.0.1+dfsg-5","26.0.1+dfsg-6","26.0.1+dfsg-7","26.0.1+dfsg-8","26.0.1+dfsg-9","27.0.0+dfsg-2","27.0.0+dfsg-3","27.0.0+dfsg-4","28.0.1+dfsg-1","28.0.1+dfsg-2","28.0.1+dfsg-3","29.0.1+dfsg-1","29.0.1+dfsg-2","29.0.1+dfsg-3","29.0.1+dfsg-4","29.0.1+dfsg-5","29.0.1+dfsg-6","29.0.1+dfsg-7","29.0.1+dfsg-8","36.0.11+dfsg-1","36.0.12+dfsg-1","36.0.12+dfsg-2","36.0.12+dfsg-3","36.0.13+dfsg-1","36.0.5+dfsg-1","36.0.5+dfsg-2","36.0.5+dfsg-3","36.0.5+dfsg-4","36.0.5+dfsg-5","36.0.6+dfsg-1","36.0.6+dfsg-2","36.0.6+dfsg-3","36.0.6+dfsg-4","36.0.6+dfsg-5","36.0.6+dfsg-6","36.0.6+dfsg-7","36.0.7+dfsg-1","36.0.8+dfsg-1","36.0.9+dfsg-1","36.0.9+dfsg-2"]},{"source":"osv","ecosystem":"crates.io","package":"wasmtime-wasi","ranges":[{"type":"SEMVER","events":[{"introduced":"0.0.0-0"},{"fixed":"36.0.17"},{"introduced":"37.0.0"},{"fixed":"48.0.4"},{"introduced":"49.0.0"},{"fixed":"49.0.2"}]}]},{"source":"osv","ecosystem":"Ubuntu:24.04:LTS","package":"rust-wasmtime","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["10.0.1+dfsg-7","15.0.1+dfsg-4","16.0.0+dfsg-2","16.0.0+dfsg-3"]},{"source":"osv","ecosystem":"Ubuntu:26.10","package":"rust-wasmtime","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["36.0.5+dfsg-1","36.0.13+dfsg-1"]},{"source":"osv","ecosystem":"Ubuntu:26.04:LTS","package":"rust-wasmtime","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["26.0.1+dfsg-3","26.0.1+dfsg-4","28.0.1+dfsg-3","29.0.1+dfsg-5","36.0.5+dfsg-1"]}],"products":[{"vendor":"bytecodealliance","product":"wasmtime"}],"references":[{"url":"https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-96f6-r43r-8c24","tags":["vendor-advisory","advisory","report"]},{"url":"https://www.vulncheck.com/advisories/wasmtime-before-36.0.17-37.0.0-before-48.0.4-and-49.0.0-before-49.0.2-memory-disclosure-via-fd-readdir","tags":["third-party-advisory","advisory","report"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-115386","tags":["advisory"]},{"url":"https://github.com/advisories/GHSA-7vfm-vg2r-wpmh"},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/115xxx/CVE-2026-115386.json","tags":["advisory"]},{"url":"https://security-tracker.debian.org/tracker/CVE-2026-115386","tags":["advisory"]},{"url":"https://crates.io/crates/wasmtime-wasi","tags":["package"]},{"url":"https://rustsec.org/advisories/RUSTSEC-2026-0323.html","tags":["advisory"]},{"url":"https://github.com/bytecodealliance/wasmtime/pull/14487","tags":["web"]},{"url":"https://ubuntu.com/security/CVE-2026-115386","tags":["report"]},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-115386","tags":["report"]}],"sources":{"cve":[{"id":"CVE-2026-115386","title":"Wasmtime before 36.0.17, 37.0.0 before 48.0.4, and 49.0.0 before 49.0.2 Memory Disclosure via fd_readdir","description":"Wasmtime before 36.0.17, 37.0.0 before 48.0.4, and 49.0.0 before 49.0.2 contains an information disclosure vulnerability in the WASIp1 fd_readdir implementation that copies uninitialized struct padding into guest memory. Guests with a preopened directory can list entries to receive three bytes of leftover host stack or heap memory per directory entry.","status":"published","published":"2026-10-22T19:13:52.931Z","modified":"2026-10-23T15:00:52.816Z","cvss":[{"version":"4.0","score":2.1,"vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:P/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N","level":"low","assessor":"cna"},{"version":"3.1","score":2.6,"vector":"CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:L/I:N/A:N","level":"low","assessor":"cna"}],"cwes":["CWE-908"],"updated_at":"2026-11-02T14:20:01.618694Z"}],"euvd":[{"id":"EUVD-2026-108314","description":"Wasmtime before 36.0.17, 37.0.0 before 48.0.4, and 49.0.0 before 49.0.2 contains an information disclosure vulnerability in the WASIp1 fd_readdir implementation that copies uninitialized struct padding into guest memory. Guests with a preopened directory can list entries to receive three bytes of leftover host stack or heap memory per directory entry.","status":"published","published":"2026-10-22T19:13:52Z","modified":"2026-10-23T15:00:52Z","cvss":[{"version":"4.0","score":2.1,"vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:P/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N","level":"low"}],"updated_at":"2026-11-02T16:59:32.223152Z"}],"ghsa":[{"id":"GHSA-7vfm-vg2r-wpmh","title":"Wasmtime before 36.0.17, 37.0.0 before 48.0.4, and 49.0.0 before 49.0.2 contains an information...","description":"Wasmtime before 36.0.17, 37.0.0 before 48.0.4, and 49.0.0 before 49.0.2 contains an information disclosure vulnerability in the WASIp1 fd_readdir implementation that copies uninitialized struct padding into guest memory. Guests with a preopened directory can list entries to receive three bytes of leftover host stack or heap memory per directory entry.","status":"published","published":"2026-10-22T21:32:43Z","modified":"2026-10-22T21:32:47Z","cvss":[{"version":"4.0","score":2.1,"vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:P/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","level":"low"},{"version":"3.1","score":2.6,"vector":"CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:L/I:N/A:N","level":"low"}],"cwes":["CWE-908"],"updated_at":"2026-11-02T15:14:18.215402Z"}],"nvd":[{"id":"CVE-2026-115386","description":"Wasmtime before 36.0.17, 37.0.0 before 48.0.4, and 49.0.0 before 49.0.2 contains an information disclosure vulnerability in the WASIp1 fd_readdir implementation that copies uninitialized struct padding into guest memory. Guests with a preopened directory can list entries to receive three bytes of leftover host stack or heap memory per directory entry.","status":"published","published":"2026-10-22T19:17:45.857Z","modified":"2026-10-23T15:17:29.22Z","cvss":[{"version":"4.0","score":2.1,"vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:P/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","level":"low","assessor":"secondary"},{"version":"3.1","score":2.6,"vector":"CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:L/I:N/A:N","level":"low","assessor":"secondary"}],"cwes":["CWE-908"],"updated_at":"2026-11-02T14:13:02.724605Z"}],"osv":[{"id":"CVE-2026-115386","title":"Wasmtime before 36.0.17, 37.0.0 before 48.0.4, and 49.0.0 before 49.0.2 Memory Disclosure via fd_readdir","description":"Wasmtime before 36.0.17, 37.0.0 before 48.0.4, and 49.0.0 before 49.0.2 contains an information disclosure vulnerability in the WASIp1 fd_readdir implementation that copies uninitialized struct padding into guest memory. Guests with a preopened directory can list entries to receive three bytes of leftover host stack or heap memory per directory entry.","status":"published","published":"2026-10-22T19:13:52.931Z","modified":"2026-10-28T02:30:46.706628748Z","cvss":[{"version":"4.0","score":2.1,"vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:P/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N","level":"low"}],"cwes":["CWE-908"],"updated_at":"2026-11-02T15:44:56.675758Z"},{"id":"DEBIAN-CVE-2026-115386","description":"Wasmtime before 36.0.17, 37.0.0 before 48.0.4, and 49.0.0 before 49.0.2 contains an information disclosure vulnerability in the WASIp1 fd_readdir implementation that copies uninitialized struct padding into guest memory. Guests with a preopened directory can list entries to receive three bytes of leftover host stack or heap memory per directory entry.","status":"published","published":"2026-10-22T19:17:45.857Z","modified":"2026-11-02T22:00:07.66980734Z","cvss":[{"version":"4.0","score":2.1,"vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:P/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","level":"low"}],"updated_at":"2026-11-03T00:03:07.015763Z"},{"id":"RUSTSEC-2026-0323","title":"fd_readdir copies uninitialized struct padding into guest memory","description":"This is an entry in the RustSec database for the Wasmtime security advisory\nlocated at\nhttps://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-96f6-r43r-8c24\nFor more information see the GitHub-hosted security advisory.","status":"published","published":"2026-10-02T12:00:00Z","modified":"2026-10-24T06:25:41Z","cvss":[{"version":"4.0","score":2.1,"vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:P/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N","level":"low"}],"updated_at":"2026-11-02T15:53:40.430679Z"},{"id":"UBUNTU-CVE-2026-115386","description":"Wasmtime before 36.0.17, 37.0.0 before 48.0.4, and 49.0.0 before 49.0.2 contains an information disclosure vulnerability in the WASIp1 fd_readdir implementation that copies uninitialized struct padding into guest memory. Guests with a preopened directory can list entries to receive three bytes of leftover host stack or heap memory per directory entry.","status":"published","published":"2026-10-22T19:17:00Z","modified":"2026-10-28T17:50:37Z","cvss":[{"version":"3.1","score":2.6,"vector":"CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:L/I:N/A:N","level":"low"},{"version":"4.0","score":2.1,"vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:P/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N","level":"low"}],"updated_at":"2026-11-02T16:56:00.081948Z"}]}}