Medium severity · published Oct 22, 2026
CVE-2026-115379
Wasmtime 47.0.0 before 48.0.4 and 49.0.0 before 49.0.2 GC Heap Corruption via try_call
New
5.7
CVSS
0.3%
EPSS
No
On KEV
Description
Wasmtime 47.0.0 before 48.0.4 and 49.0.0 before 49.0.2 contains a missing GC rooting vulnerability that leaves references live across try_call unrooted when compiling Wasm modules. Attackers can supply Wasm modules whose callee triggers garbage collection, leaving stale or dangling references that cause GC heap corruption or incorrect execution.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
Required
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 20% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
WA
wasmtime · bytecodealliance
47.0.0 before 48.0.4; 49.0.0 before 49.0.2 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-115379
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-115379
github.com
https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-hw8m-q44c-ggrf
www.vulncheck.com
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-try-call
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