Goal Reached Thanks to every supporter — we hit 100%!

Goal: 1000 CNY · Raised: 1359 CNY

100%
Buy Us a Coffee

CVE-2026-119133— Wasmtime 47.0.0 before 48.0.6 and 49.0.0 before 49.0.3 Misaligned VMContext via Exception Tags

Quick assessment

Affected
bytecodealliance wasmtime
Exploitation
No confirmed in-the-wild exploitation; assess based on exposure
Recommended action
Check the vendor advisory and references for a fixed version. If immediate upgrade is impossible, restrict exposure and increase monitoring.

Wasmtime 47.0.0 至 48.0.6 之前的版本，以及 49.0.0 至 49.0.3 之前的版本，存在一个内存对齐缺陷：其 VMContext 布局在模块包含奇数个异常标签（exception tags）时会导致未定义行为。当启用异常功能时，具有奇数标签数量的 WebAssembly 模块会使嵌入环境中后续的主机字段发生错位；目前尚未发现可利用的攻击路径。

CVSS 2.6 · Low

Possible ATT&CK Techniques 1 AI

T1190 · Exploit Public-Facing Application
Get alerts for future matching vulnerabilities Log in to subscribe

I. Basic Information for CVE-2026-119133

Vulnerability Information
Have questions about the vulnerability? See if Shenlong's analysis helps!
View Shenlong Deep Dive ↗

Although we use advanced large model technology, its output may still contain inaccurate or outdated information.Shenlong tries to ensure data accuracy, but please verify and judge based on the actual situation.

Vulnerability Title
Wasmtime 47.0.0 before 48.0.6 and 49.0.0 before 49.0.3 Misaligned VMContext via Exception Tags
Source: CVE Program / CVE List V5
Vulnerability Description
Wasmtime 47.0.0 before 48.0.6 and 49.0.0 before 49.0.3 contains a memory misalignment flaw in VMContext layout that causes undefined behavior when modules contain an odd number of exception tags. A WebAssembly module with an odd tag count misaligns subsequent host fields in embedders with exceptions enabled, although no exploitation path is currently known.
Source: CVE Program / CVE List V5
CVSS Information
CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:N/I:L/A:N
Source: CVE Program / CVE List V5
Vulnerability Type
依赖未定义、未指明或实现定义的行为
Source: CVE Program / CVE List V5

Affected Products

Vendor Product Affected Versions CPE Subscribe
bytecodealliance wasmtime 47.0.0 ~ 48.0.6 -

II. Public POCs for CVE-2026-119133

# POC Description Source Link Shenlong Link
AI-Generated POC Premium

No public POC found.

Login to generate AI POC

III. Intelligence Information for CVE-2026-119133

请登录查看更多情报信息。

Other References for CVE-2026-119133 (2)

Same Patch Batch · bytecodealliance · 2026-10-29 · 14 CVEs total

CVE-2026-119134 6.2 MEDIUM Wasmtime before 36.0.18, 37.0.0 before 48.0.6, and 49.0.0 before 49.0.3 Unbounded Memory G
CVE-2026-119137 5.3 MEDIUM Wasmtime 42.0.0 before 48.0.6 and 49.0.0 before 49.0.3 Stack Overflow via Type Registry
CVE-2026-119141 5.3 MEDIUM Wasmtime 46.0.0 before 48.0.6 and 49.0.0 before 49.0.3 Host Panic via realloc
CVE-2026-119131 5.3 MEDIUM Wasmtime 46.0.0 before 48.0.6 and 49.0.0 before 49.0.3 Host Panic via wasi-http
CVE-2026-119142 4.8 MEDIUM Wasmtime 46.0.0 before 48.0.6 and 49.0.0 before 49.0.3 Host Panic via call_async Drop
CVE-2026-119138 4.8 MEDIUM Wasmtime 46.0.0 before 48.0.6 and 49.0.0 before 49.0.3 Panic After Trap
CVE-2026-119143 4.8 MEDIUM Wasmtime 46.0.0 before 48.0.6 and 49.0.0 before 49.0.3 Panic via Zero-Length Stream Writes
CVE-2026-119136 4.8 MEDIUM Wasmtime 42.0.0 before 48.0.6 and 49.0.0 before 49.0.3 Async-Entrypoint Enforcement Bypass
CVE-2026-119140 4.8 MEDIUM Wasmtime 46.0.0 before 48.0.6 and 49.0.0 before 49.0.3 Host Panic via thread.yield
CVE-2026-119132 4.8 MEDIUM Wasmtime 49.0.0 before 49.0.3 Host Panic via Overlapping String Transcode in Fused Adapter
CVE-2026-119139 4.8 MEDIUM Wasmtime 46.0.0 before 48.0.6 and 49.0.0 before 49.0.3 Host Panic via Func::call
CVE-2026-119135 4.8 MEDIUM Wasmtime 46.0.0 before 48.0.6 and 49.0.0 before 49.0.3 Panic via StreamReader Type Mismatc
CVE-2026-119130 2.6 LOW Wasmtime before 36.0.18, 37.0.0 before 48.0.6, and 49.0.0 before 49.0.3 HTTP Request Targe

IV. Related Vulnerabilities

Same product: wasmtime
Same vendor: bytecodealliance
Same weakness: CWE-758