CVE-2026-118688
Full vulnerability record from the local CVENow database.
Description
wasmtime-wasi in Wasmtime before 36.0.18, 37.0.0 before 48.0.6, and 49.0.0 before 49.0.3 re-appends a trailing slash to rename source paths, causing renameat on macOS and FreeBSD hosts to follow directory symlinks. A guest with sandbox write access can rename a relative symlink such as "up/" to move host directories into its sandbox and read or write them.
Severity
HIGH
CVSS score
8.8
(v4.0)
Vulnerability status
Deferred
Source identifier
Published
2026-10-28 19:17:35.973000
Last modified
2026-10-28 19:17:36.090000
View original CVE JSON
{
"id": "CVE-2026-118688",
"sourceIdentifier": "[email protected]",
"published": "2026-10-28T19:17:35.973",
"lastModified": "2026-10-28T19:17:36.090",
"vulnStatus": "Deferred",
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "wasmtime-wasi in Wasmtime before 36.0.18, 37.0.0 before 48.0.6, and 49.0.0 before 49.0.3 re-appends a trailing slash to rename source paths, causing renameat on macOS and FreeBSD hosts to follow directory symlinks. A guest with sandbox write access can rename a relative symlink such as \"up/\" to move host directories into its sandbox and read or write them."
}
],
"affected": [
{
"source": "[email protected]",
"affectedData": [
{
"vendor": "bytecodealliance",
"product": "wasmtime",
"defaultStatus": "unaffected",
"packageURL": "pkg:cargo/wasmtime-wasi",
"versions": [
{
"version": "0",
"lessThan": "36.0.18",
"versionType": "semver",
"status": "affected"
},
{
"version": "36.0.18",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "37.0.0",
"lessThan": "48.0.6",
"versionType": "semver",
"status": "affected"
},
{
"version": "48.0.6",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "49.0.0",
"lessThan": "49.0.3",
"versionType": "semver",
"status": "affected"
},
{
"version": "49.0.3",
"versionType": "semver",
"status": "unaffected"
}
]
}
]
}
],
"metrics": {
"cvssMetricV40": [
{
"source": "[email protected]",
"type": "Secondary",
"cvssData": {
"version": "4.0",
"vectorString": "CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:P/VC:H/VI:H/VA:L/SC:H/SI:H/SA:L/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",
"baseScore": 8.8,
"baseSeverity": "HIGH",
"attackVector": "NETWORK",
"attackComplexity": "LOW",
"attackRequirements": "PRESENT",
"privilegesRequired": "LOW",
"userInteraction": "PASSIVE",
"vulnConfidentialityImpact": "HIGH",
"vulnIntegrityImpact": "HIGH",
"vulnAvailabilityImpact": "LOW",
"subConfidentialityImpact": "HIGH",
"subIntegrityImpact": "HIGH",
"subAvailabilityImpact": "LOW",
"exploitMaturity": "NOT_DEFINED",
"confidentialityRequirement": "NOT_DEFINED",
"integrityRequirement": "NOT_DEFINED",
"availabilityRequirement": "NOT_DEFINED",
"modifiedAttackVector": "NOT_DEFINED",
"modifiedAttackComplexity": "NOT_DEFINED",
"modifiedAttackRequirements": "NOT_DEFINED",
"modifiedPrivilegesRequired": "NOT_DEFINED",
"modifiedUserInteraction": "NOT_DEFINED",
"modifiedVulnConfidentialityImpact": "NOT_DEFINED",
"modifiedVulnIntegrityImpact": "NOT_DEFINED",
"modifiedVulnAvailabilityImpact": "NOT_DEFINED",
"modifiedSubConfidentialityImpact": "NOT_DEFINED",
"modifiedSubIntegrityImpact": "NOT_DEFINED",
"modifiedSubAvailabilityImpact": "NOT_DEFINED",
"Safety": "NOT_DEFINED",
"Automatable": "NOT_DEFINED",
"Recovery": "NOT_DEFINED",
"valueDensity": "NOT_DEFINED",
"vulnerabilityResponseEffort": "NOT_DEFINED",
"providerUrgency": "NOT_DEFINED"
}
}
],
"cvssMetricV31": [
{
"source": "[email protected]",
"type": "Primary",
"cvssData": {
"version": "3.1",
"vectorString": "CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:C/C:H/I:H/A:L",
"baseScore": 7.9,
"baseSeverity": "HIGH",
"attackVector": "NETWORK",
"attackComplexity": "HIGH",
"privilegesRequired": "LOW",
"userInteraction": "REQUIRED",
"scope": "CHANGED",
"confidentialityImpact": "HIGH",
"integrityImpact": "HIGH",
"availabilityImpact": "LOW"
},
"exploitabilityScore": 1.3,
"impactScore": 6.0
}
]
},
"weaknesses": [
{
"source": "[email protected]",
"type": "Primary",
"description": [
{
"lang": "en",
"value": "CWE-61"
}
]
}
],
"references": [
{
"url": "https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-m9f7-9w4p-gv38",
"source": "[email protected]"
},
{
"url": "https://www.vulncheck.com/advisories/wasmtime-before-36.0.18-37.0.0-before-48.0.6-and-49.0.0-before-49.0.3-sandbox-escape-via-symlink-rename",
"source": "[email protected]"
}
]
}