#VU51455 Incorrect Conversion between Numeric Types in Gnome GLib - CVE-2021-27218

Vulnerability identifier: #VU51455

Vulnerability risk: Low

CVSSv4.0: 1.1 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2021-27218

CWE-ID: CWE-681

Exploitation vector: Local

Exploit availability: No

Vulnerable software:
Gnome GLib
Universal components / Libraries / Libraries used by multiple products

Vendor: Gnome Development Team

Description

The vulnerability allows a local user to bypass implemented security restrictions.

The vulnerability exists due to incorrect conversion between numeric types in Gnome Glib. If g_byte_array_new_take() was called with a buffer of 4GB or more on a 64-bit platform, the length would be truncated modulo 2**32, causing unintended length truncation.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Gnome GLib: 2.66.0 - 2.67.3

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External links
https://gitlab.gnome.org/GNOME/glib/-/merge_requests/1942
https://gitlab.gnome.org/GNOME/glib/-/merge_requests/1944
https://lists.apache.org/thread.html/rf9fa47ab66495c78bb4120b0754dd9531ca2ff0430f6685ac9b07772@%3Cdev.mina.apache.org%3E

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Q & A

Can this vulnerability be exploited remotely?

No. This vulnerability can be exploited locally. The attacker should have authentication credentials and successfully authenticate on the system.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.