Garbage Collection Vulnerability in Wasmtime by Bytecode Alliance
CVE-2026-115379

6.9MEDIUM

Key Information:

Vendor

Bytecodealliance

Status
Wasmtime
Vendor
CVE Published:
22 October 2026

What is CVE-2026-115379?

The missing garbage collection rooting vulnerability in Wasmtime prior to versions 48.0.4 and 49.0.2 allows attackers to exploit unrooted references across try_call when compiling WebAssembly modules. This can lead to heap corruption or incorrect execution due to stale references persisting in memory, posing a significant risk during garbage collection events initiated by malicious WebAssembly modules.

Affected Version(s)

wasmtime 47.0.0 < 48.0.4

wasmtime 49.0.0 < 49.0.2

wasmtime 48.0.4

References

https://github.com/bytecodealliance/wasmtime/security/adv...
vendor-advisory
https://www.vulncheck.com/advisories/wasmtime-47.0.0-befo...
third-party-advisory

CVSS V4

Score:
6.9
Severity:
MEDIUM
Confidentiality:
None
Integrity:
None
Availability:
High
Attack Vector:
Network
Attack Complexity:
Low
Attack Required:
None
Privileges Required:
Undefined
User Interaction:
Unknown

Timeline

  • Vulnerability published

  • Vulnerability Reserved

.