OverlayFS---CVE-2021-3493

摘要 了解 OverlayFS 中的一个漏洞如何允许 Ubuntu 下的本地用户获得 root 权限。 漏洞摘要 Linux 内核中 overlayfs 文件系统的一个 Ubuntu 特定问题，它没有正确验证文件系统能力在用户命名空间方面的应用。由于 Ubuntu 中允许非特权 overlayfs 挂载的补丁，本地攻击者可以利用此漏洞提升权限。 CVE-2021-3493 致谢 一位独立安全研究员已向 SSD 安全披露计划报告了此漏洞。 受影响的版本 Ubuntu 20.10 Ubuntu 20.04 LTS Ubuntu 18.04 LTS Ubuntu 16.04 LTS Ubunt...

CVE-2021-3493

CVE-2021-3493 — Ubuntu OverlayFS 本地权限提升 CVE-2021-3493 的一个可用的概念验证（PoC）——这是 Ubuntu 内核 OverlayFS 实现中的一个本地权限提升漏洞。 非特权用户可以在用户命名空间内挂载 overlay 文件系统，并通过 setxattr 设置任意文件能力（file capabilities）。内核未能验证这些能力的命名空间来源，因此它们会在 init 用户命名空间 中生效——从而允许任何本地用户提升至 root 权限。 受影响版本 此漏洞为 Ubuntu 特有 。Ubuntu 携带了一个允许非特权 overlay...

CVE-2023-0386_POC

Team CVE-MD 本仓库提供了CVE-2023-0386的概念验证： https://nvd.nist.gov/vuln/detail/CVE-2023-0386 团队成员：Bǎnicǎ Dragoș-Marius 和 Borsos Matheas-Roland 视频链接： https://www.youtube.com/watch?v=Ikux1rjIYP0 CVE-2023-0386 — Linux OverlayFS 本地权限提升（PoC） 概述 本仓库包含针对 CVE-2023-0386 的 概念验证（PoC）利用代码 ，该漏洞是 Linux 内核 OverlayFS...

Astra Linux – Vulnerability in Linux

The overlayfs implementation in the Linux kernel failed to properly validate, regarding user namespaces, the setting of file capabilities on files in the underlying file system. Due to the combination of unprivileged user namespaces and a patch carried in the Ubuntu kernel that allows unprivilege...

USN-8193-2 libcap2 vulnerability

USN-8193-1 fixed a vulnerability in libcap. This update provides the corresponding update for Ubuntu 14.04 LTS, Ubuntu 16.04 LTS, Ubuntu 18.04 LTS, and Ubuntu 20.04 LTS. Original advisory details: Ali Raza discovered that libcap incorrectly handled file capability updates. A local attacker could...

uutils coreutils has a Time-of-Check to Time-of-Use (TOCTOU) race condition

A Time-of-Check to Time-of-Use TOCTOU vulnerability exists in the mv utility of uutils coreutils during cross-device moves. The extended attribute xattr preservation logic uses multiple path-based system calls that perform fresh path-to-inode lookups for each operation. A local attacker with writ...

GHSA-X4MC-MQM7-GG39 uutils coreutils has a Time-of-Check to Time-of-Use (TOCTOU) race condition

A Time-of-Check to Time-of-Use TOCTOU vulnerability exists in the mv utility of uutils coreutils during cross-device moves. The extended attribute xattr preservation logic uses multiple path-based system calls that perform fresh path-to-inode lookups for each operation. A local attacker with writ...

EUVD-2026-24990

A Time-of-Check to Time-of-Use TOCTOU vulnerability exists in the mv utility of uutils coreutils during cross-device moves. The extended attribute xattr preservation logic uses multiple path-based system calls that perform fresh path-to-inode lookups for each operation. A local attacker with writ...

CVE-2026-35354 uutils coreutils mv Security Xattr TOCTOU Race in Cross-Device

A Time-of-Check to Time-of-Use TOCTOU vulnerability exists in the mv utility of uutils coreutils during cross-device moves. The extended attribute xattr preservation logic uses multiple path-based system calls that perform fresh path-to-inode lookups for each operation. A local attacker with writ...

PT-2026-34490

A Time-of-Check to Time-of-Use TOCTOU vulnerability exists in the mv utility of uutils coreutils during cross-device moves. The extended attribute xattr preservation logic uses multiple path-based system calls that perform fresh path-to-inode lookups for each operation. A local attacker with writ...

Linux Distros Unpatched Vulnerability : CVE-2021-3493

The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available. - The overlayfs implementation in the linux kernel did not properly validate with respect to user namespaces the setting of file capabilities on files in an...

DEBIAN-CVE-2022-49296

In the Linux kernel, the following vulnerability has been resolved: ceph: fix possible deadlock when holding Fwb to get inlinedata 1, mount with wsync. 2, create a file with ORDWR, and the request was sent to mds.0: cephatomicopen-- cephmdscdorequestopenc finishopenfile, dentry, cephopen--...

GHSA-C9CP-9C75-9V8C containerd started with non-empty inheritable Linux process capabilities

Impact A bug was found in containerd where containers were incorrectly started with non-empty inheritable Linux process capabilities, creating an atypical Linux environment and enabling programs with inheritable file capabilities to elevate those capabilities to the permitted set during execve2...

CVE-2022-3466 Cri-o: security regression of cve-2022-27652

The version of cri-o as released for Red Hat OpenShift Container Platform 4.9.48, 4.10.31, and 4.11.6 via RHBA-2022:6316, RHBA-2022:6257, and RHBA-2022:6658, respectively, included an incorrect version of cri-o missing the fix for CVE-2022-27652, which was previously fixed in OCP 4.9.41 and 4.10....

GameOver(lay): Two Severe Linux Vulnerabilities Impact 40% of Ubuntu Users

Cybersecurity researchers have disclosed two high-severity security flaws in the Ubuntu kernel that could pave the way for local privilege escalation attacks. Cloud security firm Wiz, in a report shared with The Hacker News, said the easy-to-exploit shortcomings have the potential to impact 40% o...

MGASA-2023-0213 Updated skopeo/buildah/podman packages fix security vulnerability

Information disclosure flaw was found in Buildah CVE-2021-3602 podman allows forwarding hosts ports to vm from within vm CVE-2021-4024 Allows use "../" separators in containernetworking/cni to reference binaries such as 'reboot' in network configuration CVE-2021-20206 github.com/containers/storag...

kernel: FUSE filesystem low-privileged user privileges escalation

A flaw was found in the Linux kernel, where unauthorized access to the execution of the setuid file with capabilities was found in the Linux kernel’s OverlayFS subsystem in how a user copies a capable file from a nosuid mount into another mount. This uid mapping bug allows a local user to escalat...

K54635192: Linux kernel overlayfs vulnerability CVE-2021-3493

Security Advisory Description The overlayfs implementation in the linux kernel did not properly validate with respect to user namespaces the setting of file capabilities on files in an underlying file system. Due to the combination of unprivileged user namespaces along with a patch carried in the...

SUSE CVE-2010-2198

lib/fsm.c in RPM 4.8.0 and earlier does not properly reset the metadata of an executable file during replacement of the file in an RPM package upgrade or deletion of the file in an RPM package removal, which might allow local users to gain privileges or bypass intended access restrictions by...

USN-5776-1: containerd vulnerabilities

It was discovered that containerd incorrectly handled memory when receiving certain faulty Exec or ExecSync commands. A remote attacker could possibly use this issue to cause a denial of service or crash containerd. CVE-2022-23471, CVE-2022-31030 It was discovered that containerd incorrectly set ...