{
  "threat_severity" : "Moderate",
  "public_date" : "2026-04-09T18:32:56Z",
  "bugzilla" : {
    "description" : "wasmtime: Wasmtime: Denial of Service via improper string alignment verification",
    "id" : "2457011",
    "url" : "https://bugzilla.redhat.com/show_bug.cgi?id=2457011"
  },
  "cvss3" : {
    "cvss3_base_score" : "5.6",
    "cvss3_scoring_vector" : "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:N/I:N/A:H",
    "status" : "draft"
  },
  "cwe" : "CWE-823",
  "details" : [ "Wasmtime is a runtime for WebAssembly. Prior to 24.0.7, 36.0.7, 42.0.2, and 43.0.1, Wasmtime's implementation of transcoding strings into the Component Model's utf16 or latin1+utf16 encodings improperly verified the alignment of reallocated strings. This meant that unaligned pointers could be passed to the host for transcoding which would trigger a host panic. This panic is possible to trigger from malicious guests which transfer very specific strings across components with specific addresses. Host panics are considered a DoS vector in Wasmtime as the panic conditions are controlled by the guest in this situation. This vulnerability is fixed in 24.0.7, 36.0.7, 42.0.2, and 43.0.1.", "A flaw was found in Wasmtime, a runtime for WebAssembly. This vulnerability allows a malicious guest to trigger a host panic by improperly verifying the alignment of reallocated strings during transcoding. By transferring specific strings across components, an attacker can exploit this to cause a Denial of Service (DoS) on the host system, making it unavailable." ],
  "package_state" : [ {
    "product_name" : "Red Hat Connectivity Link 1",
    "fix_state" : "Fix deferred",
    "package_name" : "redhat-user-workloads/rhcl-1-3-wasm-shim",
    "cpe" : "cpe:/a:redhat:connectivity_link:1"
  }, {
    "product_name" : "Red Hat Enterprise Linux 10",
    "fix_state" : "Fix deferred",
    "package_name" : "virt-firmware-rs",
    "cpe" : "cpe:/o:redhat:enterprise_linux:10"
  } ],
  "references" : [ "https://www.cve.org/CVERecord?id=CVE-2026-34942\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-34942\nhttps://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-jxhv-7h78-9775" ],
  "name" : "CVE-2026-34942",
  "mitigation" : {
    "value" : "Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.",
    "lang" : "en:us"
  },
  "csaw" : false
}