6.9 Medium

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

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 4.0 detail

CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

Exploitable remotely over the network, with an ordinary account and if a user takes an action; an attacker can seriously compromise confidentiality, integrity or availability.

Attack vector: Network
Attack complexity: Low
Attack requirements: None
Privileges required: Low
Interaction: Passive
Confidentiality: None
Integrity: None
Availability: High
Confidentiality of other systems: None
Integrity of other systems: None
Availability of other systems: None

Affected products and versions

Product	Affected versions	Fixed in
wasmtime 49.0	49.0.0 → < 49.0.2	49.0.2
wasmtime 48.0	earliest → < 48.0.4	48.0.4
wasmtime 47.0	47.0.0 → < 48.0.4	48.0.4

References

GitHub Security Advisory (GHSA-hw8m-q44c-ggrf) github.com
VulnCheck Advisory: Wasmtime 47.0.0 before 48.0.4 and 49.0.0 before 49.0.2 GC Heap Corruption via try_call www.vulncheck.com

Timeline

Published October 22, 2026
Last modified November 4, 2026

The 81 CVEs of wasmtime →

CVE-2026-121441 Wasmtime before 36.0.19, 37.0.0 before 48.0.7, and 49.0.0 before 49.0.4 contains a request smuggling vulnerability in… 6.3 Medium CVE-2026-121440 Wasmtime 46.0.0 before 48.0.7 and 49.0.0 before 49.0.4 fails to check forwarded trailers against the… 6.3 Medium CVE-2026-121439 Wasmtime 46.0.0 before 48.0.7 and 49.0.0 before 49.0.4 contains a response splitting vulnerability in wasi-http p3… 6.9 Medium CVE-2026-119143 Wasmtime 46.0.0 before 48.0.6 and 49.0.0 before 49.0.3 Panic via Zero-Length Stream Writes 5.9 Medium

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