cbcvebase.
CVE-2021-1870
published 2021-04-02

CVE-2021-1870: A logic issue was addressed with improved restrictions. This issue is fixed in macOS Big Sur 11.2, Security Update 2021-001 Catalina, Security Update 2021-001…

PriorityP185critical9.8CVSS 3.1
AVNACLPRNUINSUCHIHAH
KEVITW
CISA Known Exploited Vulnerabilitydue 2021-11-17
Exploited in the wild
EPSS
7.92%
94.0th percentile
A logic issue was addressed with improved restrictions. This issue is fixed in macOS Big Sur 11.2, Security Update 2021-001 Catalina, Security Update 2021-001 Mojave, iOS 14.4 and iPadOS 14.4. A remote attacker may be able to cause arbitrary code execution. Apple is aware of a report that this issue may have been actively exploited..

Affected

14 ranges
VendorProductVersion rangeFixed in
appleios_14.4_and_ipados
appleios_and_ipados>= unspecified < 14.414.4
appleipados< 14.414.4
appleiphone_os< 14.414.4
applemac_os_x
applemac_os_x>= 10.15 < 10.15.710.15.7
applemacos>= 11.0.1 < 11.211.2
applemacos>= unspecified < 11.211.2
applemacos_big_sur_11.2_security_update_2021-001_catalina_security_update_2021-001_mo
debianwebkit2gtk< webkit2gtk 2.30.6-1 (bookworm)webkit2gtk 2.30.6-1 (bookworm)
debianwpewebkit< webkit2gtk 2.30.6-1 (bookworm)webkit2gtk 2.30.6-1 (bookworm)
fedoraprojectfedora
fedoraprojectfedora
webkitgtkwebkitgtk< 2.30.62.30.6

Detection & IOCsextracted from sources · hover to see the quote

  • CVE-2021-1870 is a logic issue in WebKit (not a memory corruption); detection should focus on anomalous remote code execution originating from WebKit rendering processes rather than typical heap/stack exploitation patterns
  • Flag unpatched WebKitGTK / WPE WebKit instances with versions prior to 2.30.6 on Linux hosts as vulnerable and actively exploitable
  • Apple confirmed in-the-wild exploitation; treat any unpatched Apple device running iOS/iPadOS < 14.4 or macOS < Big Sur 11.2 as actively at risk and prioritize detection/patching
  • ·Affected WebKitGTK/WPE WebKit versions are strictly those prior to 2.30.6; Red Hat notes webkit2gtk3 on RHEL 9 is NOT affected, and webkitgtk3 on RHEL 7 will not be fixed — scope detection rules accordingly
  • ·The Debian security tracker classifies scope as 'local' for its packages, which may affect how network-based detection rules are tuned for Debian-derived Linux environments

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
vulncheck9.8CRITICAL
cisa9.8CRITICAL
vendor_debian9.8CRITICAL
vendor_redhat9.8CRITICAL
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