Medium 4.8Published Oct 22, 2026

CVE-2026-115383Wasmtime 47.0.0 before 48.0.4 and 49.0.0 before 49.0.2 GC Heap Corruption via Tag Imports

Updated under an hour ago (Oct 28, 2026, 8:00 AM ET)

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Every CVE for bytecodealliance wasmtime

Exploited in the last 30 days

Wasmtime 47.0.0 before 48.0.4 and 49.0.0 before 49.0.2 contains an improper validation vulnerability that accepts components whose core modules import WebAssembly tags with a subtype of the original type. Malicious guests can mis-type exception object payloads to corrupt the GC heap, causing Wasmtime to panic when the exceptions proposal is enabled.

CVSS: 4.8 MEDIUM (v3.1, CNA)CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:N/I:N/A:H
Weakness (CWE): CWE-1287
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: VulnCheck
NVD analysis: Deferred
Record last updated: Oct 22, 2026
First seen by InfoSec Signals: Oct 22, 2026

Affected products

Affected products

bytecodealliance wasmtime bytecodealliance:wasmtime (from the name)	from 47.0.0 before 48.0.4; 48.0.4 not affected; from 49.0.0 before 49.0.2; 49.0.2 not affected	CNA record

References

References

https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-cfhf-m2cr-62wj	vendor-advisory
https://www.vulncheck.com/advisories/wasmtime-47.0.0-before-48.0.4-and-49.0.0-before-49.0.2-gc-heap-corruption-via-tag-imports	third-party-advisory

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.