cbcvebase.
CVE-2018-8372
published 2018-08-15

CVE-2018-8372: A remote code execution vulnerability exists in the way the scripting engine handles objects in memory in Microsoft browsers, aka "Scripting Engine Memory…

PriorityP260high7.5CVSS 3.0
AVNACHPRNUIRSUCHIHAH
EXPLOIT
EPSS
24.77%
97.6th percentile
A remote code execution vulnerability exists in the way the scripting engine handles objects in memory in Microsoft browsers, aka "Scripting Engine Memory Corruption Vulnerability." This affects ChakraCore, Internet Explorer 11, Microsoft Edge. This CVE ID is unique from CVE-2018-8353, CVE-2018-8355, CVE-2018-8359, CVE-2018-8371, CVE-2018-8373, CVE-2018-8385, CVE-2018-8389, CVE-2018-8390.

Affected

14 ranges
VendorProductVersion rangeFixed in
microsoftchakracore<= 1.10.1
microsoftchakracore
microsoftinternet_explorer
microsoftinternet_explorer
microsoftinternet_explorer
microsoftmicrosoft_edge
microsoftmicrosoft_edge
microsoftmicrosoft_edge
microsoftmicrosoft_edge
microsoftmicrosoft_edge
microsoftmicrosoft_edge
msrcchakracore
msrcinternet_explorer_11
msrcmicrosoft_edge

Detection & IOCsextracted from sources · hover to see the quote

commandmemset(buggy, -524286, 1)
  • CVE-2018-8372 is a type confusion vulnerability in Microsoft Edge's Chakra scripting engine triggered via OP_Memset when the 'value' argument equals the MissingItem value (-524286 / 0xFFF80002), which bypasses the patched input checks on native arrays.
  • Exploit pattern uses a Proxy object assigned to __proto__ of a buggy array combined with getPrototypeOf overridden to Object.prototype.valueOf to set up the type confusion primitive.
  • The vulnerability is exploitable via a specially crafted website targeting Microsoft Edge/IE scripting engine, or via an ActiveX control embedded in an Office document hosting the browser rendering engine.
  • ·The exploit-db PoC (45889) targets the bypass of the CVE-2018-8372 patch rather than the original CVE-2018-8372 vulnerability itself; the OP_Memset 'value' argument check was not included in the original patch.
  • ·Microsoft's exploit status at time of advisory was 'Publicly Disclosed: No; Exploited: No' but rated 'Exploitation More Likely' for the latest software release.

CVSS provenance

nvdv3.07.5HIGHCVSS:3.0/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H
nvdv2.07.6HIGHAV:N/AC:H/Au:N/C:C/I:C/A:C
ghsa7.5HIGH
osv7.5HIGH
vulncheck7.5HIGH
vendor_msrc4.2MEDIUM
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