cbcvebase.
CVE-2017-2455
published 2017-04-02

CVE-2017-2455: An issue was discovered in certain Apple products. iOS before 10.3 is affected. Safari before 10.1 is affected. tvOS before 10.2 is affected. The issue…

PriorityP264high8.8CVSS 3.0
AVNACLPRNUIRSUCHIHAH
EXPLOIT
EPSS
6.77%
93.2th percentile
An issue was discovered in certain Apple products. iOS before 10.3 is affected. Safari before 10.1 is affected. tvOS before 10.2 is affected. The issue involves the "WebKit" component. It allows remote attackers to execute arbitrary code or cause a denial of service (memory corruption and application crash) via a crafted web site.

Affected

7 ranges
VendorProductVersion rangeFixed in
appleios
appleiphone_os<= 10.2.1
applesafari<= 10.0.3
applesafari
appletvos<= 10.1.1
appletvos
debianwebkit2gtk< webkit2gtk 2.16.3-2 (bookworm)webkit2gtk 2.16.3-2 (bookworm)

Detection & IOCsextracted from sources · hover to see the quote

commanddiv.style.setProperty("-webkit-flow-into", "foo"); document.execCommand("fontSize", false, 6); window.requestAnimationFrame(cb); h1.attachShadow({mode: "open"}); h1.replaceWith("foo");
  • Exploit triggers a WebKit RenderLayer Use-After-Free by combining CSS -webkit-flow-into property manipulation, execCommand('fontSize'), requestAnimationFrame callback, Shadow DOM attachment (attachShadow), and DOM node replacement (replaceWith) in sequence to corrupt memory during garbage collection sweep.
  • Crash occurs inside JSC::MarkedBlock::Handle::sweep during garbage collection triggered by the exploit's loop, indicating the use-after-free is reached via the JSC heap sweeper — monitor for renderer crashes originating from JavaScriptCore GC sweep paths following Shadow DOM / CSS named flow manipulation.
  • ·Vulnerability is fixed in iOS 10.3, Safari 10.1, and tvOS 10.2; exploit only affects unpatched versions of these Apple products.
  • ·Debian WebKitGTK packages are resolved/fixed at version 2.16.3-2 across all tracked branches (bookworm, bullseye, forky, sid, trixie).

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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