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CVE-2026-115389low2.3

Wasmtime before 36.0.16, 37.0.0 before 48.0.3, and 49.0.0 before 49.0.1 Denial of Service via Val API

Impact

Wasmtime versions before 36.0.16, 37.0.0 before 48.0.3, and 49.0.0 before 49.0.1 may be vulnerable to denial of service. A malicious WebAssembly guest can cause excessive host memory allocation. The weakness is due to inadequate accounting for host allocations through the Val API.

Summarized by @cf/meta/llama-3.3-70b-instruct-fp8-fast. Verify details against the original sources.

Affected packages

This source has no supported package-version data for matching. You can read the advisory here, but this record alone cannot power a dependency check.

Affected products

Vendor version evidence. Product records are separate from automatic dependency matching.

bytecodealliance · VulnCheck

wasmtime

6 ranges
VulnCheck version evidence

Package identity

pkg:cargo/wasmtimeExplore wasmtime →

Identity supplied by VulnCheck. Version matching requires compatible range evidence.

Compare with this publisher’s ranges. This does not inspect your installation.

affected

0 → before 36.0.16

semver versions

37.0.0 → before 48.0.3

semver versions

49.0.0 → before 49.0.1

semver versions

unaffected

36.0.16

semver versions

48.0.3

semver versions

49.0.1

semver versions

unknown

Other versions: unaffected

Original source description

Wasmtime before 36.0.16, 37.0.0 before 48.0.3, and 49.0.0 before 49.0.1 does not adequately account for host allocations when lifting guest values through the dynamically-typed Val API, bypassing the hostcall fuel limit. A malicious WebAssembly guest can return crafted values that allocate at least ~100x more host memory than tracked, causing denial of service.

Inside the record

Evidence available

Package identity
Version evidence
Remediation guidance · not supplied
Weakness classification
Additional publishers

Describes the evidence in this view, not whether the product is safe.

Original records

CVE-2026-115389

View the latest unmodified CVE JSON from the official source. It may be newer than this imported page.

cve.new JSON →

Underlying weaknesses

The source’s classification of what caused the vulnerability.

CWE-770 ↗

Allocation of Resources Without Limits or Throttling

VulnCheck

Related →

Environment requirements

These conditions apply together as specified by the publisher. A matching product name alone does not establish exposure.

VulnCheck · platform conditions

Any condition may hold

Vulnerable product

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

Before: 36.0.16

Vulnerable product

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

From (inclusive): 37.0.0

Before: 48.0.3

Vulnerable product

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

From (inclusive): 49.0.0

Before: 49.0.1

Original applicability statements
[
  {
    "nodes": [
      {
        "operator": "OR",
        "negate": false,
        "cpeMatch": [
          {
            "vulnerable": true,
            "criteria": "cpe:2.3:a:bytecodealliance:wasmtime:*:*:*:*:*:*:*:*",
            "versionEndExcluding": "36.0.16"
          },
          {
            "vulnerable": true,
            "criteria": "cpe:2.3:a:bytecodealliance:wasmtime:*:*:*:*:*:*:*:*",
            "versionStartIncluding": "37.0.0",
            "versionEndExcluding": "48.0.3"
          },
          {
            "vulnerable": true,
            "criteria": "cpe:2.3:a:bytecodealliance:wasmtime:*:*:*:*:*:*:*:*",
            "versionStartIncluding": "49.0.0",
            "versionEndExcluding": "49.0.1"
          }
        ]
      }
    ]
  }
]
Contributing organizations · 2
VulnCheck

Assigning organization

2026-10-22
CISA-ADP

Additional data publisher

2026-10-29

What changed

Follow changes
No substantive changes have been recorded here yet. History starts when cve.new observes a change after tracking is enabled; earlier edits are not reconstructed.

Large field values are marked as truncated previews. Original source snapshots remain retained.

References

2 sources
github.com/bytecodealliance/wasmtime/security/advisories/GHSA-jqpg-j7w6-42pr
vendor-advisoryVulnCheck
www.vulncheck.com/advisories/wasmtime-before-36.0.16-37.0.0-before-48.0.3-and-49.0.0-before-49.0.1-denial-of-service-via-val-api
third-party-advisoryVulnCheck