CVE-2026-43472 : Detail

CVE-2026-43472

5.5
/
Sedang
0.02%V4
2026-05-08
15h17 +00:00
Local
2026-11-06
16h18 +00:00
Notifikasi untuk CVE tertentu
Tetap terinformasi tentang perubahan untuk CVE tertentu.
Kelola notifikasi

Deskripsi CVE

In the Linux kernel, the following vulnerability has been resolved: unshare: fix unshare_fs() handling There's an unpleasant corner case in unshare(2), when we have a CLONE_NEWNS in flags and current->fs hadn't been shared at all; in that case copy_mnt_ns() gets passed current->fs instead of a private copy, which causes interesting warts in proof of correctness] > I guess if private means fs->users == 1, the condition could still be true. Unfortunately, it's worse than just a convoluted proof of correctness. Consider the case when we have CLONE_NEWCGROUP in addition to CLONE_NEWNS (and current->fs->users == 1). We pass current->fs to copy_mnt_ns(), all right. Suppose it succeeds and flips current->fs->{pwd,root} to corresponding locations in the new namespace. Now we proceed to copy_cgroup_ns(), which fails (e.g. with -ENOMEM). We call put_mnt_ns() on the namespace created by copy_mnt_ns(), it's destroyed and its mount tree is dissolved, but... current->fs->root and current->fs->pwd are both left pointing to now detached mounts. They are pinning those, so it's not a UAF, but it leaves the calling process with unshare(2) failing with -ENOMEM _and_ leaving it with pwd and root on detached isolated mounts. The last part is clearly a bug. There is other fun related to that mess (races with pivot_root(), including the one between pivot_root() and fork(), of all things), but this one is easy to isolate and fix - treat CLONE_NEWNS as "allocate a new fs_struct even if it hadn't been shared in the first place". Sure, we could go for something like "if both CLONE_NEWNS *and* one of the things that might end up failing after copy_mnt_ns() call in create_new_namespaces() are set, force allocation of new fs_struct", but let's keep it simple - the cost of copy_fs_struct() is trivial. Another benefit is that copy_mnt_ns() with CLONE_NEWNS *always* gets a freshly allocated fs_struct, yet to be attached to anything. That seriously simplifies the analysis... FWIW, that bug had been there since the introduction of unshare(2) ;-/

Informasi CVE

Kelemahan Terkait

CWE-ID Nama Kelemahan Sumber
CWE-908 Use of Uninitialized Resource
The product uses or accesses a resource that has not been initialized.

Metrik

Metrik Skor Tingkat keparahan CVSS Vektor Sumber
V3.1 5.5 MEDIUM CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Base: Exploitabilty Metrics

The Exploitability metrics reflect the characteristics of the thing that is vulnerable, which we refer to formally as the vulnerable component.

Attack Vector

This metric reflects the context by which vulnerability exploitation is possible.

Local

The vulnerable component is not bound to the network stack and the attacker’s path is via read/write/execute capabilities.

Attack Complexity

This metric describes the conditions beyond the attacker’s control that must exist in order to exploit the vulnerability.

Low

Specialized access conditions or extenuating circumstances do not exist. An attacker can expect repeatable success when attacking the vulnerable component.

Privileges Required

This metric describes the level of privileges an attacker must possess before successfully exploiting the vulnerability.

Low

The attacker requires privileges that provide basic user capabilities that could normally affect only settings and files owned by a user. Alternatively, an attacker with Low privileges has the ability to access only non-sensitive resources.

User Interaction

This metric captures the requirement for a human user, other than the attacker, to participate in the successful compromise of the vulnerable component.

None

The vulnerable system can be exploited without interaction from any user.

Base: Scope Metrics

The Scope metric captures whether a vulnerability in one vulnerable component impacts resources in components beyond its security scope.

Scope

Formally, a security authority is a mechanism (e.g., an application, an operating system, firmware, a sandbox environment) that defines and enforces access control in terms of how certain subjects/actors (e.g., human users, processes) can access certain restricted objects/resources (e.g., files, CPU, memory) in a controlled manner. All the subjects and objects under the jurisdiction of a single security authority are considered to be under one security scope. If a vulnerability in a vulnerable component can affect a component which is in a different security scope than the vulnerable component, a Scope change occurs. Intuitively, whenever the impact of a vulnerability breaches a security/trust boundary and impacts components outside the security scope in which vulnerable component resides, a Scope change occurs.

Unchanged

An exploited vulnerability can only affect resources managed by the same security authority. In this case, the vulnerable component and the impacted component are either the same, or both are managed by the same security authority.

Base: Impact Metrics

The Impact metrics capture the effects of a successfully exploited vulnerability on the component that suffers the worst outcome that is most directly and predictably associated with the attack. Analysts should constrain impacts to a reasonable, final outcome which they are confident an attacker is able to achieve.

Confidentiality Impact

This metric measures the impact to the confidentiality of the information resources managed by a software component due to a successfully exploited vulnerability.

None

There is no loss of confidentiality within the impacted component.

Integrity Impact

This metric measures the impact to integrity of a successfully exploited vulnerability. Integrity refers to the trustworthiness and veracity of information.

None

There is no loss of integrity within the impacted component.

Availability Impact

This metric measures the impact to the availability of the impacted component resulting from a successfully exploited vulnerability.

High

There is a total loss of availability, resulting in the attacker being able to fully deny access to resources in the impacted component; this loss is either sustained (while the attacker continues to deliver the attack) or persistent (the condition persists even after the attack has completed). Alternatively, the attacker has the ability to deny some availability, but the loss of availability presents a direct, serious consequence to the impacted component (e.g., the attacker cannot disrupt existing connections, but can prevent new connections; the attacker can repeatedly exploit a vulnerability that, in each instance of a successful attack, leaks a only small amount of memory, but after repeated exploitation causes a service to become completely unavailable).

Temporal Metrics

The Temporal metrics measure the current state of exploit techniques or code availability, the existence of any patches or workarounds, or the confidence in the description of a vulnerability.

Environmental Metrics

These metrics enable the analyst to customize the CVSS score depending on the importance of the affected IT asset to a user’s organization, measured in terms of Confidentiality, Integrity, and Availability.

nvd@nist.gov

EPSS

EPSS adalah model penilaian yang memprediksi kemungkinan suatu kerentanan dieksploitasi.

Skor EPSS

Model EPSS menghasilkan skor probabilitas antara 0 dan 1 (0 hingga 100%). Semakin tinggi skor, semakin besar probabilitas bahwa suatu kerentanan akan dieksploitasi.

Persentil EPSS

Persentil digunakan untuk meranking CVE berdasarkan skor EPSS mereka. Misalnya, CVE di persentil ke-95 berdasarkan skor EPSS-nya lebih mungkin dieksploitasi daripada 95% CVE lainnya. Dengan demikian, persentil digunakan untuk membandingkan skor EPSS suatu CVE dengan CVE lainnya.

Produk yang Disebutkan

Konfigurasi 0

Linux>>Linux_kernel >> Version Dari (termasuk) 2.6.16.1 Hingga (tidak termasuk) 5.10.253

Linux>>Linux_kernel >> Version Dari (termasuk) 5.11 Hingga (tidak termasuk) 5.15.203

Linux>>Linux_kernel >> Version Dari (termasuk) 5.16 Hingga (tidak termasuk) 6.1.167

Linux>>Linux_kernel >> Version Dari (termasuk) 6.2 Hingga (tidak termasuk) 6.6.130

Linux>>Linux_kernel >> Version Dari (termasuk) 6.7 Hingga (tidak termasuk) 6.12.78

Linux>>Linux_kernel >> Version Dari (termasuk) 6.13 Hingga (tidak termasuk) 6.18.19

Linux>>Linux_kernel >> Version Dari (termasuk) 6.19 Hingga (tidak termasuk) 6.19.9

Linux>>Linux_kernel >> Version 2.6.16

Linux>>Linux_kernel >> Version 2.6.16

Linux>>Linux_kernel >> Version 2.6.16

Linux>>Linux_kernel >> Version 2.6.16

Linux>>Linux_kernel >> Version 2.6.16

Linux>>Linux_kernel >> Version 2.6.16

Linux>>Linux_kernel >> Version 7.0

Referensi