cbcvebase.
CVE-2020-9850
published 2020-06-09

CVE-2020-9850: A logic issue was addressed with improved restrictions. This issue is fixed in iOS 13.5 and iPadOS 13.5, tvOS 13.4.5, watchOS 6.2.5, Safari 13.1.1, iTunes…

PriorityP180critical9.8CVSS 3.1
AVNACLPRNUINSUCHIHAH
EXPLOIT
EPSS
77.25%
99.5th percentile
A logic issue was addressed with improved restrictions. This issue is fixed in iOS 13.5 and iPadOS 13.5, tvOS 13.4.5, watchOS 6.2.5, Safari 13.1.1, iTunes 12.10.7 for Windows, iCloud for Windows 11.2, iCloud for Windows 7.19. A remote attacker may be able to cause arbitrary code execution.

Affected

17 ranges
VendorProductVersion rangeFixed in
appleicloud< 7.197.19
appleicloud>= 11.0 < 11.211.2
appleicloud_for_windows>= unspecified < iCloud for Windows 11.2iCloud for Windows 11.2
appleicloud_for_windows>= unspecified < iCloud for Windows 7.19iCloud for Windows 7.19
appleios>= unspecified < iOS 13.5 and iPadOS 13.5iOS 13.5 and iPadOS 13.5
appleipados< 13.513.5
appleiphone_os< 13.513.5
appleitunes< 12.10.712.10.7
appleitunes_for_windows>= unspecified < iTunes 12.10.7 for WindowsiTunes 12.10.7 for Windows
applesafari< 13.1.113.1.1
applesafari>= unspecified < Safari 13.1.1Safari 13.1.1
appletvos< 13.4.513.4.5
appletvos>= unspecified < tvOS 13.4.5tvOS 13.4.5
applewatchos< 6.2.56.2.5
applewatchos>= unspecified < watchOS 6.2.5watchOS 6.2.5
debianwebkit2gtk< webkit2gtk 2.28.3-1 (bookworm)webkit2gtk 2.28.3-1 (bookworm)
debianwpewebkit< webkit2gtk 2.28.3-1 (bookworm)webkit2gtk 2.28.3-1 (bookworm)

Detection & IOCsextracted from sources · hover to see the quote

path/var/db/CVMS
  • Monitor for type confusion exploitation in Safari's DFG JIT compiler triggered via the 'in' operator with a PDF plugin element callback, which can be used to construct addrof and fakeobj primitives leading to arbitrary read/write of memory.
  • Detect shellcode written into JIT RWX memory regions (RWX memory pages) as part of the exploit chain following type confusion exploitation.
  • Alert on unexpected file extraction or application creation under /var/db/CVMS on macOS, which is used by the exploit chain to stage and execute a payload outside the sandbox.
  • Monitor for exploitation of CVM Server heap overflow (CVE-2020-9856) as a chained second-stage following the initial Safari type confusion, indicating a full exploit chain in progress.
  • ·The exploit chain requires three chained CVEs (CVE-2020-9850, CVE-2020-9856, CVE-2020-9801); detection of any single stage may not indicate full compromise without the others.
  • ·WebKitGTK-based deployments on Red Hat Enterprise Linux are rated 'Moderate' severity because no WebKitGTK-based browser is shipped by default, reducing the attack surface compared to Safari on macOS/iOS.

CVSS provenance

nvdv3.19.8CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
nvdv2.07.5HIGHAV:N/AC:L/Au:N/C:P/I:P/A:P
osv9.8CRITICAL
vendor_debian9.8CRITICAL
vendor_redhat9.8CRITICAL
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