cbcvebase.
CVE-2018-4121
published 2018-04-03

CVE-2018-4121: An issue was discovered in certain Apple products. iOS before 11.3 is affected. Safari before 11.1 is affected. iCloud before 7.4 on Windows is affected…

PriorityP265high8.8CVSS 3.0
AVNACLPRNUIRSUCHIHAH
EXPLOIT
EPSS
13.21%
96.0th percentile
An issue was discovered in certain Apple products. iOS before 11.3 is affected. Safari before 11.1 is affected. iCloud before 7.4 on Windows is affected. iTunes before 12.7.4 on Windows is affected. tvOS before 11.3 is affected. watchOS before 4.3 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

13 ranges
VendorProductVersion rangeFixed in
appleicloud< 7.47.4
appleicloud_for_windows
appleios
appleiphone_os< 11.311.3
appleitunes< 12.7.412.7.4
appleitunes_12.7.4_for_windows
applesafari< 11.111.1
applesafari
appletvos< 11.311.3
appletvos
applewatchos< 4.34.3
applewatchos
debianwebkit2gtk< webkit2gtk 2.20.0-2 (bookworm)webkit2gtk 2.20.0-2 (bookworm)

Detection & IOCsextracted from sources · hover to see the quote

urlhttps://gitlab.com/exploit-database/exploitdb-bin-sploits/-/raw/main/bin-sploits/44427.zip
  • Exploit targets WebAssembly binary parsing in WebKit — look for crafted .wasm files delivered via web content, particularly binaries with out-of-order or repeated sections (e.g., duplicate non-Custom sections)
  • The specific overflow triggered is in the function vector — monitor for crashes or memory corruption in WebKit's WebAssembly function vector during .wasm parsing
  • Exploit PoC is delivered as an HTML file paired with a .wasm file — detect suspicious HTML pages loading malformed WebAssembly binaries with repeated or misordered sections
  • Any number of sections can appear multiple times and in any order in the malicious .wasm — a WASM parser/IDS rule should flag binaries where non-Custom sections appear more than once or out of spec order
  • ·The validateOrder() logic flaw only bypasses ordering checks when the *previous* section was a Custom section — malicious .wasm files must interleave Custom sections to exploit this

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
vendor_redhat8.8HIGH
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