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

Goal: 1000 CNY · Raised: 1359 CNY

100%
Buy Us a Coffee

CVE-2026-115391— Wasmtime 46.0.0 before 46.0.3 and 47.0.0 before 47.0.4 Unbounded Heap Allocation via WASIp3 Streams

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 46.0.0 至 46.0.3 之前的版本，以及 47.0.0 至 47.0.4 之前的版本，其 WASIp3 实现中存在一个不受控的资源分配漏洞。该漏洞允许在主机端无限制地缓冲由 guest（客户端）指定长度的写入操作。恶意 guest 可向 WASIp3 的文件或 HTTP 写入流提供超大缓冲区，导致主机复制并缓存所有字节（仅受 guest 线性内存大小限制），从而耗尽主机内存。

CVSS 5.8 · Medium

Possible ATT&CK Techniques 1 AI

T1499 · Endpoint Denial of Service

Affected Version Matrix 4

VendorProduct Version RangeStatus
bytecodealliance wasmtime 46.0.0< 46.0.3 affected
46.0.3 unaffected
47.0.0< 47.0.4 affected
47.0.4 unaffected
Get alerts for future matching vulnerabilities Log in to subscribe

I. Basic Information for CVE-2026-115391

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Although we use advanced large model technology, its output may still contain inaccurate or outdated information.Shenlong tries to ensure data accuracy, but please verify and judge based on the actual situation.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 46.0.0 before 46.0.3 and 47.0.0 before 47.0.4 Unbounded Heap Allocation via WASIp3 Streams
Source: CVE Program / CVE List V5
Vulnerability Description
Wasmtime 46.0.0 before 46.0.3 and 47.0.0 before 47.0.4 contains an uncontrolled resource allocation vulnerability in its WASIp3 implementation that buffers guest-specified-length writes on the host without limit. Malicious guests can offer large buffers to WASIp3 file or HTTP write streams, causing the host to copy and buffer all bytes, bounded only by guest linear memory, exhausting host memory.
Source: CVE Program / CVE List V5
CVSS Information
CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:C/C:N/I:N/A:H
Source: CVE Program / CVE List V5
Vulnerability Type
不加限制或调节的资源分配
Source: CVE Program / CVE List V5

Affected Products

Vendor Product Affected Versions CPE Subscribe
bytecodealliance wasmtime 46.0.0 ~ 46.0.3 -

II. Public POCs for CVE-2026-115391

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

No public POC found.

Login to generate AI POC

III. Intelligence Information for CVE-2026-115391

请登录查看更多情报信息。

Other References for CVE-2026-115391 (2)

Same Patch Batch · bytecodealliance · 2026-10-22 · 15 CVEs total

CVE-2026-115384 9.9 CRITICAL Wasmtime 39.0.0 before 48.0.4 and 49.0.0 before 49.0.2 Stack Buffer Overflow
CVE-2026-115392 7.9 HIGH Wasmtime before 24.0.13, 25.0.0 before 36.0.14, 37.0.0 before 46.0.3, and 47.0.0 before 47
CVE-2026-115388 6.2 MEDIUM Wasmtime before 36.0.16, 37.0.0 before 48.0.3, and 49.0.0 before 49.0.1 Memory Exhaustion
CVE-2026-115385 6.2 MEDIUM Wasmtime 46.0.0 before 48.0.4 and 49.0.0 before 49.0.2 Host Panic via WASIp3 Timestamps
CVE-2026-115387 6.2 MEDIUM Wasmtime before 36.0.16, 37.0.0 before 48.0.3, and 49.0.0 before 49.0.1 Host Panic via WAS
CVE-2026-115390 5.7 MEDIUM Wasmtime 47.0.0 before 48.0.3 and 49.0.0 before 49.0.1 Fuel Accounting Bypass DoS
CVE-2026-115379 5.7 MEDIUM Wasmtime 47.0.0 before 48.0.4 and 49.0.0 before 49.0.2 GC Heap Corruption via try_call
CVE-2026-115382 4.8 MEDIUM Wasmtime 46.0.0 before 48.0.4 and 49.0.0 before 49.0.2 wasi:http Zero Timeout Panic DoS
CVE-2026-115381 4.8 MEDIUM Wasmtime before 36.0.17, 37.0.0 before 48.0.4, and 49.0.0 before 49.0.2 Unbounded Host Mem
CVE-2026-115383 4.8 MEDIUM Wasmtime 47.0.0 before 48.0.4 and 49.0.0 before 49.0.2 GC Heap Corruption via Tag Imports
CVE-2026-115380 4.0 MEDIUM Wasmtime before 36.0.17, 37.0.0 before 48.0.4, and 49.0.0 before 49.0.2 Fuel Limit Bypass
CVE-2026-115393 3.8 LOW Wasmtime before 24.0.12, 25.0.0 before 36.0.13, 37.0.0 before 46.0.2, and 47.0.0 before 47
CVE-2026-115386 2.6 LOW Wasmtime before 36.0.17, 37.0.0 before 48.0.4, and 49.0.0 before 49.0.2 Memory Disclosure
CVE-2026-115389 2.3 LOW Wasmtime before 36.0.16, 37.0.0 before 48.0.3, and 49.0.0 before 49.0.1 Denial of Service

IV. Related Vulnerabilities

Same product: wasmtime
Same vendor: bytecodealliance
Same weakness: CWE-770

V. Comments for CVE-2026-115391

No comments yet

Leave a comment