{"id":"CVE-2026-126410","summary":"Wasmtime 48.0.0 before 48.0.8 TOCTOU UDP Send Policy Bypass via wasip3 Sockets","details":"Wasmtime's wasmtime-wasi crate 48.0.0 before 48.0.8, 49.0.0 before 49.0.5, and 50.0.0 before 50.0.1 contains a time-of-check/time-of-use race in the wasip3 wasi:sockets udp-socket host implementation that lets guests bypass socket_addr_check send restrictions. A malicious guest can race udp-socket.send against udp-socket.connect to deliver attacker-controlled datagrams to addresses the policy permits only for receiving.","aliases":["GHSA-hmmr-87qq-258j","RUSTSEC-2026-0420"],"modified":"2026-11-14T02:56:04.288898460Z","published":"2026-11-13T09:35:41.472Z","database_specific":{"cwe_ids":["CWE-367"],"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/126xxx/CVE-2026-126410.json","cna_assigner":"VulnCheck"},"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/126xxx/CVE-2026-126410.json"},{"type":"ADVISORY","url":"https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-hmmr-87qq-258j"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-126410"},{"type":"ADVISORY","url":"https://www.vulncheck.com/advisories/wasmtime-48.0.0-before-48.0.8-toctou-udp-send-policy-bypass-via-wasip3-sockets"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/bytecodealliance/wasmtime","events":[{"introduced":"f1412a598f96f3c261a19118d94caffcb0c36235"},{"fixed":"7b6c29ec3e9a49c97da231665cbd8eead9ccbda0"},{"introduced":"17830bd3c0331d920a8aa38846eebc4d46d98c23"},{"fixed":"805a0f15320e8836cf2b9f001b53d884bf866c89"},{"introduced":"ebe5e8df1f4e12c5fc2f5954926881d8d61367d8"},{"fixed":"c307ec81de02852d815e9849f7c89d955c03c30d"}],"database_specific":{"extracted_events":[{"strategy":"StandardRange","range":[{"introduced":"48.0.0"},{"fixed":"48.0.8"}],"source":"AFFECTED_FIELD"},{"range":[{"introduced":"49.0.0"},{"fixed":"49.0.5"}],"source":"AFFECTED_FIELD","strategy":"StandardRange"},{"source":"AFFECTED_FIELD","strategy":"StandardRange","range":[{"introduced":"50.0.0"},{"fixed":"50.0.1"}]}]}}],"versions":["v50.0.0","v49.0.4","v48.0.7","v48.0.6","v49.0.3","v48.0.5","v49.0.2","v48.0.4","v48.0.3","v49.0.1","v49.0.0","v48.0.2","v48.0.1","v48.0.0"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-126410.json"}}],"schema_version":"1.9.2","severity":[{"type":"CVSS_V4","score":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N"}]}