OverlayFS---CVE-2021-3493

TL;DR OverlayFS の脆弱性により、Ubuntu 上のローカルユーザーが root 権限を取得できる仕組みを解説します。 脆弱性の概要 Linux カーネルの overlayfs ファイルシステムに関する Ubuntu 固有の問題で、ユーザー名前空間に関連するファイルシステムケーパビリティの適用を適切に検証していませんでした。Ubuntu が非特権 overlayfs マウントを許可するために取り込んだパッチにより、ローカルの攻撃者はこれを利用して特権を昇格させることができました。 CVE-2021-3493 クレジット 独立したセキュリティ研究者が、この脆弱性を SSD...

CVE-2021-3493

CVE-2021-3493 — Ubuntu OverlayFS Local Privilege Escalation A working proof-of-concept for CVE-2021-3493 , a local privilege escalation vulnerability in the Ubuntu kernel's OverlayFS implementation. An unprivileged user can mount an overlay filesystem inside a user namespace and set arbitrary fil...

CVE-2023-0386_POC

Team CVE-MD Dieses Repository enthält einen Proof-of-Concept für CVE-2023-0386: https://nvd.nist.gov/vuln/detail/CVE-2023-0386 Teammitglieder: Bǎnicǎ Dragoș-Marius und Borsos Matheas-Roland Hier ist das Video: https://www.youtube.com/watch?v=Ikux1rjIYP0 CVE-2023-0386 — Lokale Privilegienerweiteru...

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...

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...

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...

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 ...