{"id":"CVE-2026-126407","aliases":["EUVD-2026-125036","GHSA-2gjh-4jcm-q34v","GHSA-6fr9-xmw9-5352","RUSTSEC-2026-0424","UBUNTU-CVE-2026-126407"],"status":"published","title":"Wasmtime before 36.0.20 Denial of Service via Borrowed Resource Transfer","description":"Wasmtime before 36.0.20, 37.0.0 before 48.0.8, 49.0.0 before 49.0.5, and 50.0.0 before 50.0.1 allocates untracked host memory when a component receives a borrow of a resource it defines itself, bypassing the per-store handle limit. A malicious guest component can repeatedly transfer such borrowed resources to consume arbitrary host memory, causing denial of service.","severity":{"version":"4.0","score":5.9,"vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N","level":"medium","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-14","score":0.0031,"percentile":0.24188,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-770"],"published":"2026-10-29T12:00:00Z","modified":"2026-11-14T02:55:59Z","fixes":[{"ecosystem":"crates.io","package":"wasmtime","fixed_in":["36.0.20","48.0.8","49.0.5","50.0.1"],"sources":["osv"]}],"affected":[{"source":"osv","ecosystem":"crates.io","package":"wasmtime","ranges":[{"type":"SEMVER","events":[{"introduced":"0.0.0-0"},{"fixed":"36.0.20"},{"introduced":"37.0.0"},{"fixed":"48.0.8"},{"introduced":"49.0.0"},{"fixed":"49.0.5"},{"introduced":"50.0.0"},{"fixed":"50.0.1"}]}]},{"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-6fr9-xmw9-5352","tags":["vendor-advisory","advisory","report"]},{"url":"https://www.vulncheck.com/advisories/wasmtime-before-36.0.20-denial-of-service-via-borrowed-resource-transfer","tags":["third-party-advisory","advisory","report"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-126407","tags":["advisory"]},{"url":"https://github.com/advisories/GHSA-2gjh-4jcm-q34v"},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/126xxx/CVE-2026-126407.json","tags":["advisory"]},{"url":"https://crates.io/crates/wasmtime","tags":["package"]},{"url":"https://rustsec.org/advisories/RUSTSEC-2026-0424.html","tags":["advisory"]},{"url":"https://github.com/bytecodealliance/wasmtime/pull/15075","tags":["web"]},{"url":"https://ubuntu.com/security/CVE-2026-126407","tags":["report"]},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-126407","tags":["report"]}],"sources":{"cve":[{"id":"CVE-2026-126407","title":"Wasmtime before 36.0.20 Denial of Service via Borrowed Resource Transfer","description":"Wasmtime before 36.0.20, 37.0.0 before 48.0.8, 49.0.0 before 49.0.5, and 50.0.0 before 50.0.1 allocates untracked host memory when a component receives a borrow of a resource it defines itself, bypassing the per-store handle limit. A malicious guest component can repeatedly transfer such borrowed resources to consume arbitrary host memory, causing denial of service.","status":"published","published":"2026-11-13T09:35:43.638Z","modified":"2026-11-13T15:55:30.553Z","cvss":[{"version":"4.0","score":5.9,"vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N","level":"medium","assessor":"cna"},{"version":"3.1","score":4.8,"vector":"CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:N/I:N/A:H","level":"medium","assessor":"cna"}],"cwes":["CWE-770"],"updated_at":"2026-11-13T10:27:12.184616Z"}],"euvd":[{"id":"EUVD-2026-125036","description":"Wasmtime before 36.0.20, 37.0.0 before 48.0.8, 49.0.0 before 49.0.5, and 50.0.0 before 50.0.1 allocates untracked host memory when a component receives a borrow of a resource it defines itself, bypassing the per-store handle limit. A malicious guest component can repeatedly transfer such borrowed resources to consume arbitrary host memory, causing denial of service.","status":"published","published":"2026-11-13T09:35:43Z","modified":"2026-11-13T15:55:30Z","cvss":[{"version":"4.0","score":5.9,"vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N","level":"medium"}],"updated_at":"2026-11-13T14:38:51.723487Z"}],"ghsa":[{"id":"GHSA-2gjh-4jcm-q34v","title":"Wasmtime before 36.0.20, 37.0.0 before 48.0.8, 49.0.0 before 49.0.5, and 50.0.0 before 50.0.1...","description":"Wasmtime before 36.0.20, 37.0.0 before 48.0.8, 49.0.0 before 49.0.5, and 50.0.0 before 50.0.1 allocates untracked host memory when a component receives a borrow of a resource it defines itself, bypassing the per-store handle limit. A malicious guest component can repeatedly transfer such borrowed resources to consume arbitrary host memory, causing denial of service.","status":"published","published":"2026-11-13T12:31:22Z","modified":"2026-11-13T12:31:28Z","cvss":[{"version":"4.0","score":5.9,"vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:P/VC:N/VI:N/VA:H/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":"medium"},{"version":"3.1","score":4.8,"vector":"CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:N/I:N/A:H","level":"medium"}],"cwes":["CWE-770"],"updated_at":"2026-11-13T12:50:13.746549Z"}],"nvd":[{"id":"CVE-2026-126407","description":"Wasmtime before 36.0.20, 37.0.0 before 48.0.8, 49.0.0 before 49.0.5, and 50.0.0 before 50.0.1 allocates untracked host memory when a component receives a borrow of a resource it defines itself, bypassing the per-store handle limit. A malicious guest component can repeatedly transfer such borrowed resources to consume arbitrary host memory, causing denial of service.","status":"published","published":"2026-11-13T10:17:45.637Z","modified":"2026-11-13T16:18:23.423Z","cvss":[{"version":"4.0","score":5.9,"vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:P/VC:N/VI:N/VA:H/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":"medium","assessor":"secondary"},{"version":"3.1","score":4.8,"vector":"CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:N/I:N/A:H","level":"medium","assessor":"secondary"}],"cwes":["CWE-770"],"updated_at":"2026-11-13T17:36:48.454406Z"}],"osv":[{"id":"CVE-2026-126407","title":"Wasmtime before 36.0.20 Denial of Service via Borrowed Resource Transfer","description":"Wasmtime before 36.0.20, 37.0.0 before 48.0.8, 49.0.0 before 49.0.5, and 50.0.0 before 50.0.1 allocates untracked host memory when a component receives a borrow of a resource it defines itself, bypassing the per-store handle limit. A malicious guest component can repeatedly transfer such borrowed resources to consume arbitrary host memory, causing denial of service.","status":"published","published":"2026-11-13T09:35:43.638Z","modified":"2026-11-14T02:55:59.002516813Z","cvss":[{"version":"4.0","score":5.9,"vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N","level":"medium"}],"cwes":["CWE-770"],"updated_at":"2026-11-14T03:11:06.681237Z"},{"id":"UBUNTU-CVE-2026-126407","description":"Wasmtime before 36.0.20, 37.0.0 before 48.0.8, 49.0.0 before 49.0.5, and 50.0.0 before 50.0.1 allocates untracked host memory when a component receives a borrow of a resource it defines itself, bypassing the per-store handle limit. A malicious guest component can repeatedly transfer such borrowed resources to consume arbitrary host memory, causing denial of service.","status":"published","published":"2026-11-13T00:00:00Z","modified":"2026-11-13T21:05:25.506134583Z","cvss":[{"version":"3.1","score":4.8,"vector":"CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:N/I:N/A:H","level":"medium"},{"version":"4.0","score":5.9,"vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N","level":"medium"}],"updated_at":"2026-11-13T21:30:20.292037Z"},{"id":"RUSTSEC-2026-0424","title":"Unchecked memory usage in transferring borrowed resources between components","description":"This is an entry in the RustSec database for the Wasmtime security advisory\nlocated at\nhttps://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-6fr9-xmw9-5352\nFor more information see the GitHub-hosted security advisory.","status":"published","published":"2026-10-29T12:00:00Z","modified":"2026-11-14T02:55:59.002516813Z","updated_at":"2026-11-14T03:11:06.681237Z"}]}}