CVE-2020-9934

published 2020-10-16

CVE-2020-9934: An issue existed in the handling of environment variables. This issue was addressed with improved validation. This issue is fixed in iOS 13.6 and iPadOS 13.6…

Priority P2 77 medium 5.5 CVSS 3.1

AV L AC L PR L UI N S U C H I N A N

KEV ITW EXPLOIT

An issue existed in the handling of environment variables. This issue was addressed with improved validation. This issue is fixed in iOS 13.6 and iPadOS 13.6, macOS Catalina 10.15.6. A local user may be able to view sensitive user information.

Affected

7 ranges

Vendor	Product	Version range	Fixed in
apple	ios	>= unspecified < iOS 13.6 and iPadOS 13.6	iOS 13.6 and iPadOS 13.6
apple	ios_13.6_and_ipados	—	—
apple	ipados	< 13.6	13.6
apple	iphone_os	< 13.6	13.6
apple	mac_os_x	< 10.15.6	10.15.6
apple	macos	>= unspecified < macOS Catalina 10.15.6	macOS Catalina 10.15.6
apple	macos_catalina_10.15.6_security_update_2020-004_mojave_security_update_2020-004	—	—

Detection & IOCs extracted from sources · hover to see the quote

• → The TCC daemon can be manipulated by setting the HOME environment variable to a user-controlled location, causing tccd to use an attacker-supplied TCC database instead of the legitimate one. Monitor for unusual HOME environment variable values set in processes spawned under tccd or its children. ↗
• → Monitor for INSERT operations into a user-controlled TCC database file (e.g., TCC.db in a non-standard HOME path) that grant TCC entitlements to arbitrary processes. ↗
• → The vulnerable component is CoreFoundation on macOS Catalina <= 10.15.5, iOS 13.x, and iPadOS 13.x. Scope detection efforts to these platform/version combinations. ↗

• · This is a local privilege/entitlement escalation vulnerability; exploitation requires local user access. Remote exploitation is not applicable. ↗
• · The affected component is CoreFoundation (TCC daemon, tccd). Detections should be scoped to macOS Catalina <= 10.15.5, iOS <= 13.5, and iPadOS <= 13.5, as the fix was introduced in macOS Catalina 10.15.6, iOS 13.6, and iPadOS 13.6. ↗

CVSS provenance

nvd v3.1 5.5 MEDIUM CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N

nvd v2.0 2.1 LOW AV:L/AC:L/Au:N/C:P/I:N/A:N

vulncheck 5.5 MEDIUM

cisa 5.5 MEDIUM

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