CVE-2026-34946Disclosure(bytecodealliance / wasmtime)

LOWCVSS 7.5 · HIGH

Signal is active with 2 mentions in latest observed window

Immediate actions

  • Track advisory updates for patch or workaround availability

Recommended action window: Monitor and triage in normal cycle

NVD description

Wasmtime is a runtime for WebAssembly. From 25.0.0 to before 36.0.7, 42.0.2, and 43.0.1, Wasmtime's Winch compiler contains a vulnerability where the compilation of the table.fill instruction can result in a host panic. This means that a valid guest can be compiled with Winch, on any architecture, and cause the host to panic. This represents a denial-of-service vulnerability in Wasmtime due to guests being able to trigger a panic. The specific issue is that a historical refactoring changed how compiled code referenced tables within the table.* instructions. This refactoring forgot to update the Winch code paths associated as well, meaning that Winch was using the wrong indexing scheme. Due to the feature support of Winch the only problem that can result is tables being mixed up or nonexistent tables being used, meaning that the guest is limited to panicking the host (using a nonexistent table), or executing spec-incorrect behavior and modifying the wrong table. This vulnerability is fixed in 36.0.7, 42.0.2, and 43.0.1.

0.0/ 10 priority

Sources & remediation

Weakness type (CWE)
CWE-670

Priority

LOW

Exploitation

NONE

PoC

NONE

Patch

NONE

Momentum

NONE

Are you affected?

If you run products in this scope, you should treat this CVE as relevant to your environment.

  • wasmtime

Threat summary

  • 2 mentions across 1 observed day

What's happening

  • Technical details provided in 2 signals
  • Disclosure: 2 classified signals
  • 2 total mentions across 1 day

Affected systems

Products
wasmtime

Deep dive

Activity timeline2 mentions / 1d
01122Mentions · 2026-04-09: 2Technical Details · 2026-04-09: 204-09
Signal classification1 categories
Disclosure
2100.0%
Referenced assets2 URLs
By indicator
Full discourse2 posts
  • Infoflowcloud@infoflowcloud
    Disclosure

    🚨*CVE* CVE-2026-34946 Wasmtime is a runtime for WebAssembly. From 25.0.0 to before 36.0.7, 42.0.2, and 43.0.1, Wasmtime's Winch compiler contains a vulnerability where the compilation of t… https://www.cve.org/CVERecord?id=CVE-2026-34946 ----- Traducción: CVE-2026-34946 Was… http://infoflow.cloud`

    Post summary

    The tweet alerts to CVE‑2026‑34946, providing affected versions of Wasmtime’s Winch compiler, but offers no PoC, exploit, or patch details.

    0000035
    67 followersView on X
  • CVE@CVEnew
    Disclosure

    CVE-2026-34946 Wasmtime is a runtime for WebAssembly. From 25.0.0 to before 36.0.7, 42.0.2, and 43.0.1, Wasmtime's Winch compiler contains a vulnerability where the compilation of t… https://www.cve.org/CVERecord?id=CVE-2026-34946

    Post summary

    The post announces CVE‑2026‑34946, outlining the affected Wasmtime compiler versions, but offers no PoC, exploit, or mitigation details.

    00000126
    57.0K followersView on X
CPE platform detail1 entries

1 of 1 entries

PartVendorProductVersionTarget SWTarget HW
Appbytecodealliancewasmtime-rust-

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