CVE-2026-115381 (GCVE-0-2026-115381)

Vulnerability from cvelistv5 – Published: 2026-10-22 19:13 – Updated: 2026-10-22 19:13
VLAI
Title
Wasmtime before 36.0.17, 37.0.0 before 48.0.4, and 49.0.0 before 49.0.2 Unbounded Host Memory Allocation via SinkOutputStream write-zeroes
Summary
Wasmtime before 36.0.17, 37.0.0 before 48.0.4, and 49.0.0 before 49.0.2 contains an unbounded memory allocation in the wasmtime-wasi WASIp2 write-zeroes method of SinkOutputStream, the default stream used when stdout/stderr are not configured. A malicious WebAssembly guest can request huge zero-filled writes, exhausting host memory and causing denial of service.
Severity
5.9 (Medium)
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
4.8 (Medium)
CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:N/I:N/A:H
CWE
  • CWE-770 - Allocation of Resources Without Limits or Throttling
Assigner
VulnCheck CNA under the mitre root
CNA scorecard B 84/100 over 6762 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
bytecodealliance wasmtime Affected: 0 , < 36.0.17 (semver)
Unaffected: 36.0.17 (semver)
Affected: 37.0.0 , < 48.0.4 (semver)
Unaffected: 48.0.4 (semver)
Affected: 49.0.0 , < 49.0.2 (semver)
Unaffected: 49.0.2 (semver)
    cpe:2.3:a:bytecodealliance:wasmtime:*:*:*:*:*:*:*:*
    cpe:2.3:a:bytecodealliance:wasmtime:*:*:*:*:*:*:*:*
    cpe:2.3:a:bytecodealliance:wasmtime:*:*:*:*:*:*:*:*
Create a notification for this product.
Date Public
2026-10-02 00:00
Credits
smaeljaish771 KeenSecurityLab
Show details on NVD website
To clipboard 

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    "dateReserved": "2026-10-22T11:25:27.610Z",
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}



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