CVE-2020-9949 - Use After Free

Severity

78%

Complexity

18%

Confidentiality

98%

A use after free issue was addressed with improved memory management. This issue is fixed in macOS Big Sur 11.0.1, watchOS 7.0, iOS 14.0 and iPadOS 14.0, macOS Catalina 10.15.6, Security Update 2020-004 Mojave, Security Update 2020-004 High Sierra, tvOS 14.0. An application may be able to execute arbitrary code with kernel privileges.

CVSS 3.1 Base Score 7.8. CVSS Attack Vector: local. CVSS Attack Complexity: low. CVSS Vector: (CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H).

CVSS 2.0 Base Score 9.3. CVSS Attack Vector: network. CVSS Attack Complexity: medium. CVSS Vector: (AV:N/AC:M/Au:N/C:C/I:C/A:C).

Demo Examples

Use After Free

CWE-416

The following example demonstrates the weakness.


               
}
free(buf3R2);

Use After Free

CWE-416

The following code illustrates a use after free error:


               
}
free(ptr);
logError("operation aborted before commit", ptr);

When an error occurs, the pointer is immediately freed. However, this pointer is later incorrectly used in the logError function.

Stay updated

ExploitPedia is constantly evolving. Sign up to receive a notification when we release additional functionality.

Get in touch

If you'd like to report a bug or have any suggestions for improvements then please do get in touch with us using this form. We will get back to you as soon as we can.