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NVD / CVE Program· CNA GitHub_M

CVE-2026-44216: Wasmtime: Panic when allocating a table exceeding the size of the host's address space

MediumCVSS 5.9 · v4.0—No exploit Fix available

Noroxi assessment

Priority: Monitor (action score 23/100)

  • The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
  • Probability of exploitation in the next 30 days: 0.31% (FIRST EPSS).
  • Anyone who can reach it over the internet can trigger it. A low-privileged account is enough. No special conditions are required; it is repeatable.
  • Fixed version: bytecodealliance wasmtime 36.0.8.

Low priority for now. Upgrade to bytecodealliance wasmtime 36.0.8 or later.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

Wasmtime is a runtime for WebAssembly. From 30.0.0 to 36.0.8, 43.0.2, and 44.0.1, Wasmtime's allocation logic for a WebAssembly table contained checked arithmetic which panicked on overflow. This overflow is possible to trigger, and thus panic, when a table with an extremely large size is allocated. This is possible with the WebAssembly memory64 proposal where tables can have sizes in the 64-bit range as opposed to the previous 32-bit range which would not overflow. The panic happens when attempting to create a very large table, such as when instantiating a WebAssembly module or component. This vulnerability is fixed in 36.0.8, 43.0.2, and 44.0.1.

Published
May 14, 2026
Updated
Oct 26, 2026
EPSS
0.3% · 25th percentile

Report tools

JSON

Action score

23

Monitor

Low priority for now.

CVSS
23 / 40 · 5.9 / 10
CISA KEV
0 / 30 · Not listed
EPSS
0 / 30 · 0.3%

CISA SSVC decision

Exploitation
none
Automatable
no
Technical impact
partial

Vulnrichment: CISA's decision-tree inputs.

CNA vs NVD score

NVD
—
CNA · GitHub_M
5.9
NVD has not scored this yet; the score shown is the CNA’s.

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

The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.

Get told when this record changes

  • Not in KEV: no record of exploitation in the wild
  • No public exploit code on record
  • A fix has been released

If any of these changes, we'll tell you in the daily email digest.

Follow CVE-2026-44216

When you'll hear from us

  • when it enters CISA KEV
  • when exploit code appears or is weaponized
  • when the record is updated (including a fixed version)
  • when EPSS rises 20 points in a week

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Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

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Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

VendorProduct
bytecodealliancewasmtime

Versions reported by the vendor

Affected version ranges reported by the assigning authority (GitHub_M). Independent of NVD's CPE analysis and usually ahead of it.

  • bytecodealliance wasmtime

    • >= 30.0.0, < 36.0.8, >= 37.0.0, < 43.0.2, 44.0.0affected

Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

  • bytecodealliance wasmtime30.0.0 and later · before 36.0.8
  • bytecodealliance wasmtime37.0.0 and later · before 43.0.2
  • bytecodealliance wasmtime44.0.0

Package-level exposure

OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.

EcosystemPackageAffected rangeFix
crates.iowasmtimefrom 30.0.0 · before 36.0.836.0.8
crates.iowasmtimefrom 37.0.0 · before 43.0.243.0.2
crates.iowasmtimefrom 44.0.0 · before 44.0.144.0.1
Debian:13rust-wasmtimefrom 0—
Debian:14rust-wasmtimebefore 36.0.8+dfsg-136.0.8+dfsg-1
openSUSE:Tumbleweedtree-sitterbefore 0.26.8-3.10.26.8-3.1
Red Hat:hummingbird:1cargobefore 0:1.97.1-2.hum10:1.97.1-2.hum1
Red Hat:hummingbird:1clippybefore 0:1.97.1-2.hum10:1.97.1-2.hum1
Red Hat:hummingbird:1rustbefore 0:1.97.1-2.hum10:1.97.1-2.hum1
Red Hat:hummingbird:1rust-analyzerbefore 0:1.97.1-2.hum10:1.97.1-2.hum1
Red Hat:hummingbird:1rust-debugger-commonbefore 0:1.97.1-2.hum10:1.97.1-2.hum1
Red Hat:hummingbird:1rust-docbefore 0:1.97.1-2.hum10:1.97.1-2.hum1
Red Hat:hummingbird:1rust-gdbbefore 0:1.97.1-2.hum10:1.97.1-2.hum1
Red Hat:hummingbird:1rust-lldbbefore 0:1.97.1-2.hum10:1.97.1-2.hum1
Red Hat:hummingbird:1rust-srcbefore 0:1.97.1-2.hum10:1.97.1-2.hum1
Red Hat:hummingbird:1rust-std-staticbefore 0:1.97.1-2.hum10:1.97.1-2.hum1
Red Hat:hummingbird:1rust-std-static-aarch64-unknown-none-softfloatbefore 0:1.97.1-2.hum10:1.97.1-2.hum1
Red Hat:hummingbird:1rust-std-static-aarch64-unknown-uefibefore 0:1.97.1-2.hum10:1.97.1-2.hum1
Red Hat:hummingbird:1rust-std-static-i686-pc-windows-gnubefore 0:1.97.1-2.hum10:1.97.1-2.hum1
Red Hat:hummingbird:1rust-std-static-wasm32-unknown-unknownbefore 0:1.97.1-2.hum10:1.97.1-2.hum1
Red Hat:hummingbird:1rust-std-static-wasm32-wasip1before 0:1.97.1-2.hum10:1.97.1-2.hum1
Red Hat:hummingbird:1rust-std-static-x86_64-pc-windows-gnubefore 0:1.97.1-2.hum10:1.97.1-2.hum1
Red Hat:hummingbird:1rust-std-static-x86_64-unknown-nonebefore 0:1.97.1-2.hum10:1.97.1-2.hum1
Red Hat:hummingbird:1rust-std-static-x86_64-unknown-uefibefore 0:1.97.1-2.hum10:1.97.1-2.hum1

+2

Same product

bytecodealliance: all records

Other highest-scoring records for the same primary product.

  • CVE-2026-115893Wasmtime: Cranelift backend on aarch64 can jump to incorrect target on large Wasm `br_table` instruction
    39Monitor
  • CVE-2026-115889Wasmtime: Bit-packing in Cranelift compiler causes silent overflow and miscompilation
    39Monitor
  • CVE-2022-39394wasmtime_trap_code C API function has out of bounds write vulnerability
    39Monitor

Published before and after this one in the same product

  • ← EarlierCVE-2026-35186Apr 9, 2026 · Wasmtime has an improperly masked return value from `table.grow` with Winch compiler backend
    24Monitor
  • ← EarlierCVE-2026-35195Apr 9, 2026 · Wasmtime has an out-of-bounds write or crash when transcoding component model strings
    24Monitor
  • Later →CVE-2026-47261Jun 15, 2026 · Wasmtime: WASI path_open(TRUNCATE) bypasses `FilePerms::WRITE` host restriction
    30Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / packageFixed versionSource
bytecodealliance wasmtime36.0.8 · descriptionVendor (CNA)
crates.io:wasmtime36.0.8Package registry (OSV)
crates.io:wasmtime43.0.2Package registry (OSV)
crates.io:wasmtime44.0.1Package registry (OSV)
debian:rust-wasmtime36.0.8+dfsg-1 · Debian:14Package registry (OSV)
opensuse:tree-sitter0.26.8-3.1 · openSUSE:TumbleweedPackage registry (OSV)
red hat:cargo0:1.97.1-2.hum1 · Red Hat:hummingbird:1Package registry (OSV)
red hat:clippy0:1.97.1-2.hum1 · Red Hat:hummingbird:1Package registry (OSV)
red hat:rust0:1.97.1-2.hum1 · Red Hat:hummingbird:1Package registry (OSV)
red hat:rust-analyzer0:1.97.1-2.hum1 · Red Hat:hummingbird:1Package registry (OSV)
red hat:rust-debugger-common0:1.97.1-2.hum1 · Red Hat:hummingbird:1Package registry (OSV)
red hat:rust-doc0:1.97.1-2.hum1 · Red Hat:hummingbird:1Package registry (OSV)
red hat:rust-gdb0:1.97.1-2.hum1 · Red Hat:hummingbird:1Package registry (OSV)
red hat:rust-lldb0:1.97.1-2.hum1 · Red Hat:hummingbird:1Package registry (OSV)
red hat:rust-src0:1.97.1-2.hum1 · Red Hat:hummingbird:1Package registry (OSV)
red hat:rust-std-static0:1.97.1-2.hum1 · Red Hat:hummingbird:1Package registry (OSV)
red hat:rust-std-static-aarch64-unknown-none-softfloat0:1.97.1-2.hum1 · Red Hat:hummingbird:1Package registry (OSV)
red hat:rust-std-static-aarch64-unknown-uefi0:1.97.1-2.hum1 · Red Hat:hummingbird:1Package registry (OSV)
suse:tree-sitter0.26.8-160000.2.1 · SUSE:Linux Enterprise Server 16.0Package registry (OSV)

Exploit status

No known public exploit

No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

No dated events beyond publication.

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

  • CVE-2026-2757279 days apartWasmtime can panic when adding excessive fields to a `wasi:http/types.fields` instance
    27Monitor
  • CVE-2026-115391161 days apartWasmtime 46.0.0 before 46.0.3 and 47.0.0 before 47.0.4 Unbounded Heap Allocation via WASIp3 Streams
    27Monitor
  • CVE-2026-119134168 days apartWasmtime before 36.0.18, 37.0.0 before 48.0.6, and 49.0.0 before 49.0.3 Unbounded Memory Growth via Component-Model Resource Handles
    27Monitor
  • CVE-2026-115381161 days apartWasmtime before 36.0.17, 37.0.0 before 48.0.4, and 49.0.0 before 49.0.2 Unbounded Host Memory Allocation via SinkOutputStream write-zeroes
    23Monitor
  • CVE-2026-115380161 days apartWasmtime before 36.0.17, 37.0.0 before 48.0.4, and 49.0.0 before 49.0.2 Fuel Limit Bypass DoS via WASI Preview 0 poll_oneoff
    20Monitor
  • CVE-2026-115389161 days apartWasmtime 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
    4Monitor

Not on record for this CVE: EPSS history · patch commit or PR link · researcher credit · public bounty program.

Technical details

Attack conditions

  • Anyone who can reach it over the internet can trigger it.
  • A low-privileged account is enough.
  • No special conditions are required; it is repeatable.

If successful

Confidentiality
Integrity
Availability
Attack vector
Network
Attack complexity
Low
Privileges required
Low
User interaction
P
Scope
X

Weakness class (CWE)

CWE-770 · Allocation of Resources Without Limits or Throttling

CVSS vector

CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

nvd-secondary

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

References

Show all references (4 more)

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records