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CBL Mariner 2.0 Security Update: kernel (CVE-2024-43882)

high Nessus Plugin ID 208802

Synopsis

The remote CBL Mariner host is missing one or more security updates.

Description

The version of kernel installed on the remote CBL Mariner 2.0 host is prior to tested version. It is, therefore, affected by a vulnerability as referenced in the CVE-2024-43882 advisory.

 - In the Linux kernel, the following vulnerability has been resolved: exec: Fix ToCToU between perm check and set-uid/gid usage When opening a file for exec via do_filp_open(), permission checking is done against the file's metadata at that moment, and on success, a file pointer is passed back. Much later in the execve() code path, the file metadata (specifically mode, uid, and gid) is used to determine if/how to set the uid and gid. However, those values May have changed since the permissions check, meaning the execution May gain unintended privileges. For example, if a file could change permissions from executable and not set-id: ---------x 1 root root 16048 August 7 13:16 target to set-id and non-executable: ---S------ 1 root root 160AugustAug 7 13:16 target it is possible to gain root privileges when execution should have been disallowed. While this race condition is rare in real-world scenarios, it has been observed (and proven exploitable) when package managers are updating the setuid bits of installed programs. Such files start with being world-executable but then are adjusted to be group-exec with a set-uid bit. For example, chmod o-x,u+s target makes target executable only by uid root and gid cdrom, while also becoming setuid- root: -rwxr-xr-x 1 root cdrom August48 Aug 7 13:16 target becomes: -rwsr-xr-- 1 root cdrAugust16048 Aug 7 13:16 target But racing the chmod means users without group cdrom membership can get the permission to execute target just before the chmod, and when the chmod finishes, the exec reaches brpm_fill_uid(), and performs the setuid to root, violating the expressed authorization of only cdrom group members can setuid to root. Re-check that we still have execute permissions in case the metadata has changed. It would be better to keep a copy from the perm-check time, but until we can do that refactoring, the least-bad option is to do a full inode_permission() call (under inode lock). It is understood that this is safe against dead-locks, but hardly optimal. (CVE-2024-43882)

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

Solution

Update the affected packages.

See Also

https://nvd.nist.gov/vuln/detail/CVE-2024-43882

Plugin Details

Severity: High

ID: 208802

File Name: mariner_CVE-2024-43882.nasl

Version: 1.1

Type: local

Published: 10/13/2024

Updated: 10/13/2024

Supported Sensors: Nessus

Risk Information

VPR

Risk Factor: Medium

Score: 6.7

CVSS v2

Risk Factor: Medium

Base Score: 6

Temporal Score: 4.4

Vector: CVSS2#AV:L/AC:H/Au:S/C:C/I:C/A:C

CVSS Score Source: CVE-2024-43882

CVSS v3

Risk Factor: High

Base Score: 7

Temporal Score: 6.1

Vector: CVSS:3.0/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H

Temporal Vector: CVSS:3.0/E:U/RL:O/RC:C

Vulnerability Information

CPE: p-cpe:/a:microsoft:cbl-mariner:python3-perf, p-cpe:/a:microsoft:cbl-mariner:kernel-devel, p-cpe:/a:microsoft:cbl-mariner:kernel-tools, p-cpe:/a:microsoft:cbl-mariner:kernel-drivers-accessibility, p-cpe:/a:microsoft:cbl-mariner:kernel-drivers-gpu, x-cpe:/o:microsoft:cbl-mariner, p-cpe:/a:microsoft:cbl-mariner:kernel, p-cpe:/a:microsoft:cbl-mariner:kernel-dtb, p-cpe:/a:microsoft:cbl-mariner:bpftool, p-cpe:/a:microsoft:cbl-mariner:kernel-docs, p-cpe:/a:microsoft:cbl-mariner:kernel-drivers-sound

Required KB Items: Host/local_checks_enabled, Host/cpu, Host/CBLMariner/release, Host/CBLMariner/rpm-list

Exploit Ease: No known exploits are available

Patch Publication Date: 10/8/2024

Vulnerability Publication Date: 8/21/2024

Reference Information

CVE: CVE-2024-43882