CVE-2026-115393: Out-of-bounds Write in bytecodealliance wasmtime
Description
CVE-2026-115393 is a type confusion vulnerability in the bytecodealliance wasmtime project affecting multiple version ranges before specific fixed releases. The flaw arises because certain Store APIs do not validate that objects belong to the Store's Engine, allowing embedders to mix objects between Engines. This can cause trampoline signature mismatches leading to out-of-bounds stack writes, garbage collector heap corruption, or panics.
CVSS v4.0
Score 1.0low
Affected software
bytecodealliance
wasmtime
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AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The vulnerability exists in wasmtime versions before 24.0.12, 36.0.13, 46.0.2, and 47.0.3. It is due to several Store APIs failing to validate that objects belong to the Store's Engine, resulting in type confusion. When embedders mix objects between Engines using Instance::new, StructRefPre::new, or Tag::new, trampoline signature mismatches may occur. These mismatches can trigger out-of-bounds stack writes, corruption of the garbage collector heap, or cause panics in the runtime.
Potential Impact
Successful exploitation can lead to memory corruption such as out-of-bounds stack writes and GC heap corruption, which may destabilize the runtime environment or cause crashes (panics). The CVSS 4.0 score is low, reflecting limited attack vector and complexity, requiring local privileges and user interaction with high attack complexity.
Mitigation Recommendations
Fixed versions are available: 24.0.12, 36.0.13, 46.0.2, and 47.0.3 or later. Users should upgrade to these versions to remediate the vulnerability. No vendor advisory content was provided to indicate alternative mitigations or that no action is required.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- VulnCheck
- Date Reserved
- 2026-10-22T11:27:18.001Z
- Cvss Version
- 4.0
- State
- PUBLISHED
Threat ID: 6ada64a54d27ba8daa75658c
Added to database: 10/22/2026, 19:31:49 UTC
Last enriched: 10/22/2026, 20:30:53 UTC
Last updated: 10/22/2026, 20:55:29 UTC
Views: 9
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