// For flags

CVE-2025-43853

iwasm vulnerable to filesystem sandbox escape with symlink when using uvwasi feature

Severity Score

7.0
*CVSS v4

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

0
*Multiple Sources

Exploited in Wild

-
*KEV

Decision

Track*
*SSVC
Descriptions

The WebAssembly Micro Runtime's (WAMR) iwasm package is the executable binary built with WAMR VMcore which supports WebAssembly System Interface (WASI) and command line interface. Anyone running WAMR up to and including version 2.2.0 or WAMR built with libc-uvwasi on Windows is affected by a symlink following vulnerability. On WAMR running in Windows, creating a symlink pointing outside of the preopened directory and subsequently opening it with create flag will create a file on host outside of the sandbox. If the symlink points to an existing host file, it's also possible to open it and read its content. Version 2.3.0 fixes the issue.

*Credits: N/A
CVSS Scores
Attack Vector
Local
Attack Complexity
Low
Attack Requirements
None
Privileges Required
None
User Interaction
None
System
Vulnerable | Subsequent
Confidentiality
High
None
Integrity
Low
None
Availability
Low
None
* Common Vulnerability Scoring System
SSVC
  • Decision:Track*
Exploitation
Poc
Automatable
No
Tech. Impact
Partial
* Organization's Worst-case Scenario
Timeline
  • 2025-04-17 CVE Reserved
  • 2025-05-15 CVE Published
  • 2025-05-15 CVE Updated
  • 2025-07-22 EPSS Updated
  • ---------- Exploited in Wild
  • ---------- KEV Due Date
  • ---------- First Exploit
CWE
  • CWE-61: UNIX Symbolic Link (Symlink) Following
CAPEC
Affected Vendors, Products, and Versions
Vendor Product Version Other Status
Vendor Product Version Other Status <-- --> Vendor Product Version Other Status
Bytecodealliance
Search vendor "Bytecodealliance"
 Wasm-micro-runtime
Search vendor "Bytecodealliance" for product "Wasm-micro-runtime"
 < 2.3.0
Search vendor "Bytecodealliance" for product "Wasm-micro-runtime" and version " < 2.3.0"
en
Affected