How severe is CVE-2026-24116?

CVE-2026-24116 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2026-24116 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (12th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-24116?

CVE-2026-24116 affects Bytecodealliance Wasmtime. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-24116?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2026-24116 have an EU (EUVD) identifier?

Yes. CVE-2026-24116 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-4773.

When was CVE-2026-24116 published?

CVE-2026-24116 was published on 2026-01-27 and last updated on 2026-06-17.

CVE-2026-24116

CVE-2026-24116 is a medium-severity vulnerability in Bytecodealliance Wasmtime with a CVSS 3.x base score of 5.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-125.

Key facts

Severity: Medium (CVSS 3.x base score 5.5)
CVSS v4: 4.1
EPSS exploit prediction: 0% (12th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-4773
Weakness: CWE-125
Affected product: Bytecodealliance Wasmtime
Published: 2026-01-27
Last modified: 2026-06-17

Description

Wasmtime is a runtime for WebAssembly. Starting in version 29.0.0 and prior to version 36.0.5, 40.0.3, and 41.0.1, on x86-64 platforms with AVX, Wasmtime's compilation of the `f64.copysign` WebAssembly instruction with Cranelift may load 8 more bytes than is necessary. When signals-based-traps are disabled this can result in a uncaught segfault due to loading from unmapped guard pages. With guard pages disabled it's possible for out-of-sandbox data to be loaded, but unless there is another bug in Cranelift this data is not visible to WebAssembly guests. Wasmtime 36.0.5, 40.0.3, and 41.0.1 have been released to fix this issue. Users are recommended to upgrade to the patched versions of Wasmtime. Other affected versions are not patched and users should updated to supported major version instead. This bug can be worked around by enabling signals-based-traps. While disabling guard pages can be a quick fix in some situations, it's not recommended to disabled guard pages as it is a key defense-in-depth measure of Wasmtime.

Frequently asked questions

What is CVE-2026-24116?: Wasmtime is a runtime for WebAssembly. Starting in version 29.0.0 and prior to version 36.0.5, 40.0.3, and 41.0.1, on x86-64 platforms with AVX, Wasmtime's compilation of the `f64.copysign` WebAssembly instruction with Cranelift may load 8 more bytes than is necessary. When signals-based-traps are disabled this can result in a uncaught segfault due to loading from unmapped guard pages. With guard pages disabled it's possible for out-of-sandbox data to be loaded, but unless there is another bug in Cranelift this data is not visible to WebAssembly guests. Wasmtime 36.0.5, 40.0.3, and 41.0.1 have been released to fix this issue. Users are recommended to upgrade to the patched versions of Wasmtime. Other affected versions are not patched and users should updated to supported major version instead. This bug can be worked around by enabling signals-based-traps. While disabling guard pages can be a quick fix in some situations, it's not recommended to disabled guard pages as it is a key defense-in-depth measure of Wasmtime.
How severe is CVE-2026-24116?: CVE-2026-24116 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2026-24116 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (12th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-24116?: CVE-2026-24116 affects Bytecodealliance Wasmtime. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-24116?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-24116 have an EU (EUVD) identifier?: Yes. CVE-2026-24116 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-4773.
When was CVE-2026-24116 published?: CVE-2026-24116 was published on 2026-01-27 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:bytecodealliance:wasmtime:*:*:*:*:*:rust:*:*

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