Vulnerability-Lookup

FKIE_CVE-2026-34944

Vulnerability from fkie_nvd - Published: 2026-04-09 19:16 - Updated: 2026-04-20 18:27

Severity ?

5.7 (Medium) - CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:N/A:H

Summary

Wasmtime is a runtime for WebAssembly. Prior to 24.0.7, 36.0.7, 42.0.2, and 43.0.1, On x86-64 platforms with SSE3 disabled Wasmtime's compilation of the f64x2.splat 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 this data is not visible to WebAssembly guests. This vulnerability is fixed in 24.0.7, 36.0.7, 42.0.2, and 43.0.1.

References

	URL	Tags
	security-advisories@github.com	https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-qqfj-4vcm-26hv	Vendor Advisory

Impacted products

Vendor	Product	Version
bytecodealliance	wasmtime	*
bytecodealliance	wasmtime	*
bytecodealliance	wasmtime	*
bytecodealliance	wasmtime	*

JSON

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{
  "configurations": [
    {
      "nodes": [
        {
          "cpeMatch": [
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              "criteria": "cpe:2.3:a:bytecodealliance:wasmtime:*:*:*:*:*:rust:*:*",
              "matchCriteriaId": "5A39DBFB-CD5E-4551-8885-053DF90E277A",
              "versionEndExcluding": "24.0.7",
              "vulnerable": true
            },
            {
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            {
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              "versionEndExcluding": "42.0.2",
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    }
  ],
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  "lastModified": "2026-04-20T18:27:28.147",
  "metrics": {
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          "baseScore": 5.7,
          "baseSeverity": "MEDIUM",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "privilegesRequired": "LOW",
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          "version": "3.1"
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        "source": "nvd@nist.gov",
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    "cvssMetricV40": [
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          "Recovery": "NOT_DEFINED",
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          "attackComplexity": "LOW",
          "attackRequirements": "PRESENT",
          "attackVector": "LOCAL",
          "availabilityRequirement": "NOT_DEFINED",
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          "baseSeverity": "MEDIUM",
          "confidentialityRequirement": "NOT_DEFINED",
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          "modifiedAttackComplexity": "NOT_DEFINED",
          "modifiedAttackRequirements": "NOT_DEFINED",
          "modifiedAttackVector": "NOT_DEFINED",
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          "modifiedSubAvailabilityImpact": "NOT_DEFINED",
          "modifiedSubConfidentialityImpact": "NOT_DEFINED",
          "modifiedSubIntegrityImpact": "NOT_DEFINED",
          "modifiedUserInteraction": "NOT_DEFINED",
          "modifiedVulnAvailabilityImpact": "NOT_DEFINED",
          "modifiedVulnConfidentialityImpact": "NOT_DEFINED",
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          "privilegesRequired": "LOW",
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          "subConfidentialityImpact": "NONE",
          "subIntegrityImpact": "NONE",
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          "valueDensity": "NOT_DEFINED",
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  "vulnStatus": "Analyzed",
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    }
  ]
}

CVE-2026-34944 (GCVE-0-2026-34944)

Vulnerability from cvelistv5 – Published: 2026-04-09 18:38 – Updated: 2026-04-13 15:38

Title

Wasmtime segfault or unused out-of-sandbox load with `f64x2.splat` operator on x86-64

Summary

Severity ?

4.1 (Medium)


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

CWE

CWE-248 - Uncaught Exception

Assigner

GitHub_M

References

URL

Tags

https://github.com/bytecodealliance/wasmtime/secu…

x_refsource_CONFIRM

Impacted products

	Vendor	Product	Version
	bytecodealliance	wasmtime	Affected: < 24.0.7 Affected: >= 25.0.0, < 36.0.7 Affected: >= 37.0.0, < 42.0.2 Affected: >= 43.0.0, < 44.0.1

Show details on NVD website

JSON

To clipboard

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                "role": "CISA Coordinator",
                "timestamp": "2026-04-13T15:06:23.130132Z",
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Sightings

Author	Source	Type	Date

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

Action not permitted

FKIE_CVE-2026-34944

CVE-2026-34944 (GCVE-0-2026-34944)

Tags

Sightings

Nomenclature