Files
vuln-cve/data/2026/34xxx/CVE-2026-34987.json
T

139 lines
6.6 KiB
JSON

{
"dataType": "CVE_RECORD",
"dataVersion": "5.2",
"cveMetadata": {
"cveId": "CVE-2026-34987",
"assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
"state": "PUBLISHED",
"assignerShortName": "GitHub_M",
"dateReserved": "2026-03-31T19:38:31.617Z",
"datePublished": "2026-04-09T18:48:33.552Z",
"dateUpdated": "2026-04-10T14:12:55.374Z"
},
"containers": {
"cna": {
"title": "Wasmtime with Winch compiler backend on aarch64 may allow a sandbox-escaping memory access",
"problemTypes": [
{
"descriptions": [
{
"cweId": "CWE-125",
"lang": "en",
"description": "CWE-125: Out-of-bounds Read",
"type": "CWE"
}
]
},
{
"descriptions": [
{
"cweId": "CWE-787",
"lang": "en",
"description": "CWE-787: Out-of-bounds Write",
"type": "CWE"
}
]
}
],
"metrics": [
{
"cvssV4_0": {
"attackVector": "NETWORK",
"attackComplexity": "LOW",
"attackRequirements": "PRESENT",
"privilegesRequired": "LOW",
"userInteraction": "NONE",
"vulnConfidentialityImpact": "HIGH",
"vulnIntegrityImpact": "HIGH",
"vulnAvailabilityImpact": "HIGH",
"subConfidentialityImpact": "HIGH",
"subIntegrityImpact": "HIGH",
"subAvailabilityImpact": "HIGH",
"baseScore": 9,
"baseSeverity": "CRITICAL",
"vectorString": "CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H",
"version": "4.0"
}
}
],
"references": [
{
"name": "https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-xx5w-cvp6-jv83",
"tags": [
"x_refsource_CONFIRM"
],
"url": "https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-xx5w-cvp6-jv83"
}
],
"affected": [
{
"vendor": "bytecodealliance",
"product": "wasmtime",
"versions": [
{
"version": ">= 25.0.0, < 36.0.7",
"status": "affected"
},
{
"version": ">= 37.0.0, < 42.0.2",
"status": "affected"
},
{
"version": ">= 43.0.0, < 44.0.1",
"status": "affected"
}
]
}
],
"providerMetadata": {
"orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
"shortName": "GitHub_M",
"dateUpdated": "2026-04-09T18:48:33.552Z"
},
"descriptions": [
{
"lang": "en",
"value": "Wasmtime is a runtime for WebAssembly. From 25.0.0 to before 36.0.7, 42.0.2, and 43.0.1, Wasmtime with its Winch (baseline) non-default compiler backend may allow properly constructed guest Wasm to access host memory outside of its linear-memory sandbox. This vulnerability requires use of the Winch compiler (-Ccompiler=winch). By default, Wasmtime uses its Cranelift backend, not Winch. With Winch, the same incorrect assumption is present in theory on both aarch64 and x86-64. The aarch64 case has an observed-working proof of concept, while the x86-64 case is theoretical and may not be reachable in practice. This Winch compiler bug can allow the Wasm guest to access memory before or after the linear-memory region, independently of whether pre- or post-guard regions are configured. The accessible range in the initial bug proof-of-concept is up to 32KiB before the start of memory, or ~4GiB after the start of memory, independently of the size of pre- or post-guard regions or the use of explicit or guard-region-based bounds checking. However, the underlying bug assumes a 32-bit memory offset stored in a 64-bit register has its upper bits cleared when it may not, and so closely related variants of the initial proof-of-concept may be able to access truly arbitrary memory in-process. This could result in a host process segmentation fault (DoS), an arbitrary data leak from the host process, or with a write, potentially an arbitrary RCE. This vulnerability is fixed in 36.0.7, 42.0.2, and 43.0.1."
}
],
"source": {
"advisory": "GHSA-xx5w-cvp6-jv83",
"discovery": "UNKNOWN"
}
},
"adp": [
{
"metrics": [
{
"other": {
"type": "ssvc",
"content": {
"timestamp": "2026-04-10T14:12:37.362283Z",
"id": "CVE-2026-34987",
"options": [
{
"Exploitation": "none"
},
{
"Automatable": "no"
},
{
"Technical Impact": "total"
}
],
"role": "CISA Coordinator",
"version": "2.0.3"
}
}
}
],
"title": "CISA ADP Vulnrichment",
"providerMetadata": {
"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"shortName": "CISA-ADP",
"dateUpdated": "2026-04-10T14:12:55.374Z"
}
}
]
}
}