CVE-2018-8139

HIGH

Microsoft Edge and ChakraCore - Remote Code Execution via Scripting Engine Memory Corruption

Title source: llm
STIX 2.1

Exploitation Summary

EIP tracks 1 public exploit for CVE-2018-8139. PoCs published by Google Security Research.

AI-analyzed exploit summary This PoC exploits an out-of-bounds read vulnerability in ChakraCore's BoundFunction::NewInstance by leveraging the CallFlags_ExtraArg flag, which is mishandled when constructing argument arrays. The exploit triggers the vulnerability via Reflect.construct with a bound function, leading to an OOB read.

Description

A remote code execution vulnerability exists in the way that the scripting engine handles objects in memory in Microsoft Edge, aka "Scripting Engine Memory Corruption Vulnerability." This affects Microsoft Edge, ChakraCore. This CVE ID is unique from CVE-2018-0945, CVE-2018-0946, CVE-2018-0951, CVE-2018-0953, CVE-2018-0954, CVE-2018-0955, CVE-2018-1022, CVE-2018-8114, CVE-2018-8122, CVE-2018-8128, CVE-2018-8137.

Exploits (1)

exploitdb WORKING POC VERIFIED
by Google Security Research · javascriptdoswindows
https://www.exploit-db.com/exploits/45012

This PoC exploits an out-of-bounds read vulnerability in ChakraCore's BoundFunction::NewInstance by leveraging the CallFlags_ExtraArg flag, which is mishandled when constructing argument arrays. The exploit triggers the vulnerability via Reflect.construct with a bound function, leading to an OOB read.

Classification
Working Poc 90%
Attack Type
Dos
Complexity
Trivial
Reliability
Reliable
Target: ChakraCore (Microsoft Edge)
No auth needed
Prerequisites: A vulnerable version of ChakraCore (e.g., Microsoft Edge prior to the fix for CVE-2018-8139)
devstral-2 · analyzed Feb 16, 2026 Full analysis →

References (4)

Core 4
Core References
Third Party Advisory, VDB Entry vdb-entry x_refsource_bid
http://www.securityfocus.com/bid/103977
Exploit, Third Party Advisory, VDB Entry exploit x_refsource_exploit-db
https://www.exploit-db.com/exploits/45012/
Third Party Advisory, VDB Entry vdb-entry x_refsource_sectrack
http://www.securitytracker.com/id/1040844

Scores

CVSS v3 7.5
EPSS 0.7700
EPSS Percentile 99.0%
Attack Vector NETWORK
CVSS:3.0/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H

Details

CWE
CWE-125
Status published
Products (3)
microsoft/chakracore < 1.8.3
microsoft/edge
nuget/Microsoft.ChakraCore 0 - 1.8.4NuGet
Published May 09, 2018
Tracked Since Feb 18, 2026