cbcvebase.
CVE-2019-8506
published 2019-12-18

CVE-2019-8506: A type confusion issue was addressed with improved memory handling. This issue is fixed in iOS 12.2, tvOS 12.2, watchOS 5.2, Safari 12.1, iTunes 12.9.4 for…

PriorityP188high8.8CVSS 3.1
AVNACLPRNUIRSUCHIHAH
KEVITWEXPLOIT
CISA Known Exploited Vulnerabilitydue 2022-05-25
Exploited in the wild
EPSS
18.11%
96.9th percentile
A type confusion issue was addressed with improved memory handling. This issue is fixed in iOS 12.2, tvOS 12.2, watchOS 5.2, Safari 12.1, iTunes 12.9.4 for Windows, iCloud for Windows 7.11. Processing maliciously crafted web content may lead to arbitrary code execution.

Affected

22 ranges
VendorProductVersion rangeFixed in
appleicloud< 7.117.11
appleicloud_for_windows
appleicloud_for_windows>= unspecified < iCloud for Windows 7.11iCloud for Windows 7.11
appleios
appleios>= unspecified < iOS 12.2iOS 12.2
appleiphone_os< 12.212.2
appleitunes< 12.9.412.9.4
appleitunes_12.9.4_for_windows
appleitunes_for_windows>= unspecified < iTunes 12.9.4 for WindowsiTunes 12.9.4 for Windows
applesafari< 12.112.1
applesafari
applesafari>= unspecified < Safari 12.1Safari 12.1
appletvos< 12.212.2
appletvos
appletvos>= unspecified < tvOS 12.2tvOS 12.2
applewatchos< 5.25.2
applewatchos
applewatchos>= unspecified < watchOS 5.2watchOS 5.2
debianwebkit2gtk< webkit2gtk 2.24.1-1 (bookworm)webkit2gtk 2.24.1-1 (bookworm)
redhatenterprise_linux_desktop
redhatenterprise_linux_server
redhatenterprise_linux_workstation

Detection & IOCsextracted from sources · hover to see the quote

  • The vulnerability is triggered via String.prototype.match (regex match) on maliciously crafted web content, causing a type confusion in JavaScriptCore's createRegExpMatchesArray via putDirect without inferred type update — monitor for JIT-compiled JS exploiting regex match results with property access patterns on match.groups
  • The exploit abuses JSObject::putDirect which stores a value to a property slot without updating inferred types or firing watchpoints — this is a JavaScriptCore (WebKit) JIT type confusion; detection should focus on WebKit/Safari/WebContent process crashes or JIT code invalidation anomalies
  • ·The vulnerability only manifests when the JavaScriptCore JIT compiler (DFG/FTL) is active and has compiled code relying on inferred types for the relevant structure; disabling JIT would prevent exploitation but is not a practical production mitigation
  • ·The exploit requires a two-phase setup: first constructing the regExpMatchesArrayWithGroupsStructure with inferred types installed (before 'bad time'), then triggering the type confusion via String.prototype.match — single-pass or non-JIT execution will not trigger the bug
  • ·Fixed versions are iOS 12.2, tvOS 12.2, watchOS 5.2, Safari 12.1, iTunes 12.9.4 for Windows, iCloud for Windows 7.11; Red Hat webkitgtk (RHEL 6) is out of support scope and webkitgtk3 (RHEL 7) will not be fixed

CVSS provenance

nvdv3.18.8HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
nvdv2.09.3CRITICALAV:N/AC:M/Au:N/C:C/I:C/A:C
osv8.8HIGH
vulncheck8.8HIGH
cisa8.8HIGH
vendor_debian8.8HIGH
vendor_redhat8.8HIGH
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