Bytecode Alliance Wasmtime prior 36.0.20/48.0.8/49.0.5/50.0.1 allocation of resources

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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4.9$0-$5k0.00+

Summaryinfo

A vulnerability marked as problematic has been reported in Bytecode Alliance Wasmtime. This impacts an unknown function. Performing a manipulation results in allocation of resources. This vulnerability is reported as CVE-2026-126407. The attack is possible to be carried out remotely. No exploit exists. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability classified as problematic has been found in Bytecode Alliance Wasmtime. This affects an unknown code. The manipulation with an unknown input leads to a allocation of resources vulnerability. CWE is classifying the issue as CWE-770. The product allocates a reusable resource or group of resources on behalf of an actor without imposing any intended restrictions on the size or number of resources that can be allocated. This is going to have an impact on availability. The summary by CVE is:

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.

The advisory is shared at github.com. This vulnerability is uniquely identified as CVE-2026-126407 since 11/10/2026. The exploitability is told to be easy. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. Neither technical details nor an exploit are publicly available. MITRE ATT&CK project uses the attack technique T1499 for this issue.

Upgrading to version 36.0.20, 48.0.8, 49.0.5 or 50.0.1 eliminates this vulnerability.

If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Productinfo

Vendor

Name

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 5.1
VulDB Meta Temp Score: 4.9

VulDB Base Score: 5.3
VulDB Temp Score: 5.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 4.8
CNA Vector (VulnCheck): 🔒

CVSSv2info

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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Allocation of resources
CWE: CWE-770 / CWE-400 / CWE-404
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Wasmtime 36.0.20/48.0.8/49.0.5/50.0.1

Timelineinfo

11/10/2026 CVE reserved
11/13/2026 +3 days Advisory disclosed
11/13/2026 +0 days VulDB entry created
11/13/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: github.com
Status: Confirmed

CNA: VulnCheck
CVE: CVE-2026-126407 (🔒)

GCVE (CVE): GCVE-0-2026-126407
GCVE (VulDB): GCVE-100-436797

Entryinfo

Created: 11/13/2026 11:30
Changes: 11/13/2026 11:30 (74)
Complete: 🔍
Cache ID: 216::103

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