cbcvebase.
CVE-2018-4323
published 2019-04-03

CVE-2018-4323: Multiple memory corruption issues were addressed with improved memory handling. This issue affected versions prior to iOS 12, tvOS 12, Safari 12, iTunes 12.9…

PriorityP262high8.8CVSS 3.0
AVNACLPRNUIRSUCHIHAH
EXPLOIT
EPSS
9.61%
95.0th percentile
Multiple memory corruption issues were addressed with improved memory handling. This issue affected versions prior to iOS 12, tvOS 12, Safari 12, iTunes 12.9 for Windows, iCloud for Windows 7.7.

Affected

11 ranges
VendorProductVersion rangeFixed in
appleicloud< 7.77.7
appleicloud_for_windows
appleios
appleiphone_os< 12.012.0
appleitunes< 12.912.9
appleitunes_12.9_for_windows
applesafari< 1212
applesafari
appletvos< 1212
appletvos
debianwebkit2gtk< webkit2gtk 2.22.0-2 (bookworm)webkit2gtk 2.22.0-2 (bookworm)

Detection & IOCsextracted from sources · hover to see the quote

  • Trigger involves CSS properties: column-span:all on elements combined with -webkit-column-width on :root with position:fixed, alongside display:grid — this combination triggers the WebCore::RenderMultiColumnSet::updateMinimumColumnHeight use-after-free
  • Crash originates in WebCore::RenderMultiColumnSet::updateMinimumColumnHeight — monitor WebKit/WebCore crashes or ASan reports in this function as an indicator of exploitation attempts
  • The exploit PoC uses document.createElement('hr') appended to a DOM node inside jsfuzzer() — look for scripted DOM manipulation combined with multi-column CSS layout triggering layout recalculations via RenderBlockFlow and RenderGrid code paths
  • Vulnerability is triggered by processing maliciously crafted web content in WebKit — any WebKit-based browser (Safari, iTunes, iCloud for Windows) rendering pages with complex multi-column + CSS grid layout combinations should be treated as a potential attack vector
  • ·Fixed in WebKit2GTK 2.22.0-2 on Debian (bookworm, bullseye, forky, sid, trixie) — systems running older versions remain vulnerable
  • ·Affected Apple products include iOS prior to 12, tvOS prior to 12, Safari prior to 12, iTunes prior to 12.9 for Windows, and iCloud for Windows prior to 7.7 — all share the same vulnerable WebKit component

CVSS provenance

nvdv3.08.8HIGHCVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
nvdv2.06.8MEDIUMAV:N/AC:M/Au:N/C:P/I:P/A:P
osv8.8HIGH
vendor_debian8.8LOW
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