SB2023122303 - Gentoo update for Flatpak
Published: December 23, 2023
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 6 secuirty vulnerabilities.
1) Improper Neutralization of Special Elements in Output Used by a Downstream Component (CVE-ID: CVE-2021-21381)
The vulnerability allows a remote attacker to bypass implemented security restrictions.
The vulnerability exists due to improper input validation within the "file forwarding" feature. By putting the special tokens `@@` and/or `@@u` in the Exec field of a Flatpak app's .desktop file, a malicious app publisher can trick flatpak into behaving as though the user had chosen to open a target file with their Flatpak app, which automatically makes that file available to the Flatpak app.
2) Security restrictins bypass (CVE-ID: CVE-2021-41133)
The vulnerability allows a local user to escalate privileges on the system.
The vulnerability exists due to an error in the VFS-manipulating syscalls implementation. A local user can bypass sandbox restrictions and escalate privileges on the system.
3) Permissions, Privileges, and Access Controls (CVE-ID: CVE-2021-43860)
The vulnerability allows a remote attacker to escalate privileges on the system.
The vulnerability exists due to application does not properly validate that the permissions displayed to the user for an app at install time match the actual permissions granted to the app at runtime, which leads to security restrictions bypass and privilege escalation.
4) Path traversal (CVE-ID: CVE-2022-21682)
The vulnerability allows a remote attacker to perform directory traversal attacks.
The vulnerability exists due to input validation error when flatpak-builder applies "finish-args" last in the build. A remote authenticated attacker can send a specially crafted HTTP request and create arbitrary files on the system.
5) Input validation error (CVE-ID: CVE-2023-28100)
The vulnerability allows a malicious application to compromise the affected system.
The vulnerability exists due to insufficient validation of user-supplied input when handling copy/paste operations. If a Flatpak app is run on a Linux virtual console such as `/dev/tty1`, it can copy text from the virtual console and paste it into the command buffer, from which the command might be run after the Flatpak app has exited.
6) Input validation error (CVE-ID: CVE-2023-28101)
The vulnerability allows a remote attacker to perform spoofing attack.
The vulnerability exists due to insufficient validation of user-supplied input when displaying permissions and metadata. A remote attacker can create a specially crafted app that manipulates the appearance of the permissions list through metadata, convincing the user into granting to the app more permissions than agreed by the user.
Remediation
Install update from vendor's website.