Bytecode Alliance Wasmtime up to 36.0.17/48.0.5/49.0.2 wasmtime-wasi-http input validation

Summaryinfo

A vulnerability has been found in Bytecode Alliance Wasmtime up to 36.0.17/48.0.5/49.0.2 and classified as problematic. This issue affects some unknown processing of the component wasmtime-wasi-http. This manipulation causes input validation. This vulnerability is handled as CVE-2026-119130. The attack can be initiated remotely. There is not any exploit available. The affected component should be upgraded.

Detailsinfo

A vulnerability was found in Bytecode Alliance Wasmtime up to 36.0.17/48.0.5/49.0.2. It has been declared as problematic. Affected by this vulnerability is an unknown part of the component wasmtime-wasi-http. The manipulation with an unknown input leads to a input validation vulnerability. The CWE definition for the vulnerability is CWE-20. The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly. As an impact it is known to affect confidentiality. The summary by CVE is:

Wasmtime before 36.0.18, 37.0.0 before 48.0.6, and 49.0.0 before 49.0.3 does not verify that set-path-with-query values in wasmtime-wasi-http are paths, so absolute-form URLs are written verbatim as the HTTP/1.1 request target while the connection uses the allowed authority. A malicious guest can supply an absolute URL that a forward proxy or gateway at that authority honors, reaching hosts disallowed by embedder filtering policies.

The advisory is shared at github.com. This vulnerability is known as CVE-2026-119130 since 10/29/2026. The exploitation appears to be easy. The attack can be launched remotely. It demands that the victim is doing some kind of user interaction. Neither technical details nor an exploit are publicly available.

Upgrading to version 36.0.18, 48.0.6 or 49.0.3 eliminates this vulnerability.

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Vendor

• Bytecode Alliance

Name

• Wasmtime

Version

• 36.0.0
• 36.0.1
• 36.0.2
• 36.0.3
• 36.0.4
• 36.0.5
• 36.0.6
• 36.0.7
• 36.0.8
• 36.0.9
• 36.0.10
• 36.0.11
• 36.0.12
• 36.0.13
• 36.0.14
• 36.0.15
• 36.0.16
• 36.0.17
• 48.0.0
• 48.0.1
• 48.0.2
• 48.0.3
• 48.0.4
• 48.0.5
• 49.0.0
• 49.0.1
• 49.0.2

CPE 2.3info

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CPE 2.2info

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Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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