CVSS 4.0
5.9 mediumCVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:NCVE-2026-126407 Wasmtime before 36.0.20 Denial of Service via Borrowed Resource Transfer
Medium (5.9) in bytecodealliance wasmtime. EPSS 0.4% estimated probability of exploitation activity in the next 30 days.
On this page
Wasmtime before 36.0.20, 37.0.0 before 48.0.8, 49.0.0 before 49.0.5, and 50.0.0 before 50.0.1 allocates untracked host memory when a component receives a borrow of a resource it defines itself, bypassing the per-store handle limit. A malicious guest component can repeatedly transfer such borrowed resources to consume arbitrary host memory, causing denial of service.
Severity
CVSS 3.1
4.8 mediumCVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:N/I:N/A:H- EPSS
- 0.4% estimated probability of exploitation activity in the next 30 days; 31st percentile. Scored 2026-11-13. A forecast for this CVE across the internet, not for your own systems.
- CISA's assessment (SSVC)
- Exploitation: none · Automatable: no · Technical impact: partial, assessed 2026-11-13. From CISA's Vulnrichment in the CVE List: whether it is exploited, whether exploiting it can be automated, and how much control it gives.
- CWE
- CWE-770 Allocation of Resources Without Limits or Throttling
- Published
- Modified
- Assigned by
- VulnCheck (CNA)
- NVD analysis
- Deferred: the NVD does not plan to analyze it
- Record from
- the NVD, synced
Ask an AI about this CVE
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Affected
Versions
From the CNA's record in the CVE List.
| Product | Affected |
|---|---|
| bytecodealliance wasmtime | before 36.0.20 |
| bytecodealliance wasmtime | from 37.0.0 before 48.0.8 |
| bytecodealliance wasmtime | from 49.0.0 before 49.0.5 |
| bytecodealliance wasmtime | from 50.0.0 before 50.0.1 |
Linux distributions
| Distribution | Release | Package | Fixed in | Advisory |
|---|---|---|---|---|
| Ubuntu | 24.04:LTS, 26.04:LTS, 26.10 | rust-wasmtime | no fix listed | UBUNTU-CVE-2026-126407 |
From the distributions' data via OSV.dev: Ubuntu Security Notices © Canonical Ltd., CC BY-SA 4.0. Modified: reformatted and linked to CVE records. Credits. On the distributions' own pages: Ubuntu.
Attack patterns (CAPEC)
The attack patterns MITRE's CAPEC relates to this record's weaknesses, as MITRE names them. Credits. More on the page of CWE-770 (20).
History
- The NVD deferred its analysis
Changes since this site first stored the record. The same for every record: /api/public/changes.