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USN-8729-1: Linux kernel vulnerabilities

Ubuntu issued USN-8729-1 fixing Linux kernel vulnerabilities across ARM, Bluetooth, GPU, SCSI, SMB, and Azure MANA subsystems.

Ubuntu released USN-8729-1 addressing several security issues discovered in the Linux kernel that could allow an attacker to compromise the system. Fixes span ARM32/ARM64/PowerPC architectures, Bluetooth, GPU, InfiniBand, and network drivers, plus the Microsoft Azure Network Adapter (MANA) driver. The update also corrects flaws in the SCSI and SPI subsystems, SMB and NTFS3 file systems, EFI core, and file systems infrastructure.

Ubuntu Security Notices · 9d agoAdvisory 6 sources

Stealth rootkit targeting F5 BIG-IP could expose enterprise identity gateways

Sophos analyzed a stealth Linux rootkit that hides a web shell in memory on compromised F5 BIG-IP APM identity gateways, evading file-based detection.

Sophos analyzed a second-stage Linux rootkit implant found in compromised F5 BIG-IP APM environments running Apache and PHP, linked to exploitation of CVE-2025-53521, an unauthenticated RCE. The implant hooks Apache's PHP-loading process and serves modified in-memory versions of three legitimate webtop PHP files (apm_css.php3, full_wt.php3, webtop_popup_css.php3), leaving on-disk files untouched so hashes and integrity checks pass. It also establishes access via an authenticated local UNIX socket that can provide an interactive /bin/bash session. Experts warn compromised APM appliances, which handle federated SSO and terminate TLS at enterprise perimeters, could enable SSO token theft and lateral movement to trusted downstream applications.

CSO Online · 5d agoMalware in the wild 2 sourcesCVE-2025-53521

DPRK APTs: Ted backdoor and curlRAT target South Korean media and automotive sectors

Rapid7 uncovered a DPRK-linked Linux toolkit using a HAProxy-embedded ted backdoor, SSH keylogger, and curlRAT against South Korean media and automotive firms.

Rapid7 Labs identified a previously undocumented framework attributed with medium confidence to DPRK actors, targeting South Korean automotive and media organizations likely since early 2025. The toolkit embeds a backdoor compiled into HAProxy 2.8.12 using its filter API, plus trojanized crond, agetty, atd, sshd, and polkitd, an SSH keylogger storing credentials under /var/lib/sshd/, and a curl-based RAT with a watchdog thread. It enables remote command execution, malicious script injection into served webpages (a watering-hole loop), credential harvesting, and long-term surveillance. Hardcoded C2s are associated with APT37 via ThreatFox, and exposed groupware portals and mail servers align with Kimsuky tradecraft; the initial access vector and any CVE remain unconfirmed.

Rapid7 Blog · 11d agoThreat actor in the wild1

North Korean Hackers Deploy New Linux Espionage Toolkit

Rapid7 says North Korea-aligned actors use a new Linux espionage toolkit (ted HAProxy backdoor, CurlRAT) against South Korean automotive and media targets.

Rapid7 reports a stealthy Linux framework comprising a custom HAProxy backdoor ('ted'), trojanized system binaries (agetty, atd, crond, polkitd, sshd), an SSH keylogger, and CurlRAT that polls C&C every 12 hours. Initial access came via a Groupware login portal flaw, with credential harvesting enabling lateral movement to internal systems. The toolkit supports long-term surveillance, HTTP traffic interception/injection, and drive-by downloads, likely in use since late 2024. Infrastructure and artifacts overlap Operation SyncHole, suggesting Lazarus or APT37 involvement.

SecurityWeek · 8d agoThreat actor in the wild1

Hackers breach F5 BIG-IP APM devices to deploy Linux rootkit

Sophos analyzed a Linux rootkit on F5 BIG-IP APM devices that injects a fileless PHP web shell, likely after CVE-2025-53521 exploitation.

Sophos analyzed a Linux rootkit targeting F5 BIG-IP APM environments, also tracked by ESET as PoisonedRefresh, which hijacks Apache's apr_dso_load module loader to inject a fileless PHP web shell into memory. The implant intercepts __libc_start_main, hides strings with RC4, creates a password-protected local UNIX socket backdoor for interactive Bash access, and persists across BIG-IP upgrade images while modifying SELinux configuration. It is likely a second-stage payload following exploitation of CVE-2025-53521, a critical RCE flaw F5 reclassified from a DoS issue in March. The ShadowServer Foundation tracked 795 F5 BIG-IP APM endpoints exposed online.

BleepingComputer · 7d agoMalware in the wildCVE-2025-53521

Omarchy: Any User Process Can Escalate to Root

A security write-up details how any user process on the Omarchy Linux setup can escalate privileges to root.

A post on 0xcc.io describes a local privilege escalation issue in Omarchy, the Arch-based Linux configuration, where any user process can escalate to root. The disclosure appears to describe a design-level weakness in the distribution's security model. No CVE identifier is mentioned in the available text.

Lobsters · security · 16d agoVulnerability

APT group HoneyMyte upgrades CoolClient: the backdoor gets a kernel-level Windows rootkit

Kaspersky reports APT group HoneyMyte upgraded its CoolClient backdoor with a kernel-mode Windows rootkit hiding processes, files, and network connections.

Kaspersky researchers discovered a new variant of the HoneyMyte CoolClient backdoor equipped with a kernel-mode Windows rootkit driver. The rootkit hides malicious processes, files, and network connections from security tools and threat analysts, significantly increasing the backdoor's stealth. The report documents an upgrade to the APT group's backdoor tooling with a kernel-level implant.

Kaspersky Securelist · Aug 14, 2026Threat actor in the wild

Backdoor Xz Utils Linux Open Source

Infosecurity Magazine covers the XZ Utils open-source backdoor, a malicious implant in liblzma that targeted OpenSSH on major Linux distributions.

The article covers the XZ Utils backdoor, a malicious implant introduced into the widely used open-source compression library. The compromised liblzma code manipulated functions used by OpenSSH, nearly reaching stable releases of major Linux distributions before discovery. The incident is a prominent example of software supply chain compromise targeting critical open-source infrastructure.

Infosecurity Magazine · Aug 17, 2026VulnerabilityCVE-2024-3094

Plesk Backup Manager Flaw Lets Low-Privileged Users Gain Root Access to Servers

CVE-2026-68488 in Plesk Backup Manager lets low-privileged subscription users exploit a symlink race during restores to gain root on Linux servers.

CVE-2026-68488 is a symlink race condition in Plesk Obsidian for Linux Backup Manager during subscription-content restore operations, allowing a user with Panel and FTP access to change ownership of files outside their subscription and escalate to full root access. Affected versions are Plesk for Linux 18.0.80.6 and earlier and 18.0.79.10 and earlier; Plesk for Windows is not affected. Patches are available in 18.0.80.7 and 18.0.79.11 or later. The flaw requires valid subscription access, so it is not unauthenticated remote code execution, but successful exploitation yields complete server compromise, especially dangerous in shared-hosting and multi-tenant deployments.

UAT-10147 deploys SPECTRE: A cross-platform implant with Linux rootkit and BYOVD capabilities

Cisco Talos identifies UAT-10147 deploying the SPECTRE implant with cross-platform C2, credential theft, and kernel-level EDR bypass.

Cisco Talos reports that the tracked threat actor UAT-10147 is deploying a newly identified implant named SPECTRE. SPECTRE supports cross-platform command-and-control, process injection, credential theft, and anti-analysis protections. It also includes a Linux rootkit and BYOVD (bring your own vulnerable driver) capability enabling kernel-level EDR bypass, marking an evolution in commodity intrusion tooling.

Cisco Talos · 26d agoThreat actor in the wild

Re: Linux kernel LPEs: ZcopyReaper (CVE-2026-43502) and 20 more

oss-security thread discusses newly disclosed Linux kernel local privilege escalations, including ZcopyReaper (CVE-2026-43502) and about 20 more flaws.

An oss-security mailing list thread discusses newly disclosed Linux kernel local privilege escalation (LPE) issues, headlined by ZcopyReaper (CVE-2026-43502) along with roughly 20 more. Discussants ask whether the many reports could be summarized and note that locking kernel module loading after boot has repeatedly proven an effective mitigation. The visible discussion does not state whether any of the flaws are exploited in the wild or give specific patch guidance beyond the individual reports.

oss-security · 7d agoVulnerabilityCVE-2026-43502

PoisonedRefresh: A Fileless Linux Rootkit That Injects PHP Web Shells Into F5 BIG-IP APM Server Memory

Sophos details PoisonedRefresh, a fileless Linux rootkit that injects a memory-resident PHP web shell into F5 BIG-IP APM after exploitation of CVE-2025-53521.

On September 8, 2026, SophosLabs published an analysis of Linux/Agnt-IC (dubbed PoisonedRefresh by ESET) found in compromised F5 BIG-IP Access Policy Manager environments. Initial access leverages CVE-2025-53521, an unauthenticated RCE in BIG-IP APM when an access policy is configured on a virtual server; F5 confirmed exploitation and links the activity to cluster c05d5254, while Shadowserver observed 795 exposed vulnerable endpoints. A first stage hidden in a modified umount binary modifies /usr/sbin/httpd and SELinux configuration and embeds itself in BIG-IP upgrade images for persistence. The second-stage ELF intercepts __libc_start_main, hooks apr_dso_load, and injects a PHP web shell into libphp memory via mmap manipulation, leaving no disk artifacts, and exposes a /bin/bash shell via a local UNIX domain socket instead of a TCP port.

Security Affairs · 7d agoMalware in the wildCVE-2025-53521

TPMSpy: Validation of Measured Boot Systems by Low-Level Tracing of TPM Usage

Researchers present TPMSpy, a platform-agnostic method validating TPM Measured Boot via low-level tracing, finding inconsistent Linux systemd measurements that break remote attestation and LUKS decryption.

An arXiv paper (2609.05011) introduces TPMSpy, a method that analyzes virtualized system–TPM interactions to independently reconstruct and validate TPM Event Logs without relying on the quoting mechanism, applicable to open and closed systems and demonstrated on Linux and Windows. A longitudinal analysis of Linux systems running systemd versions 245–258 (2020–2025) found wide divergence in Measured Boot usage, undocumented behavioral changes, and no common usage pattern. The authors report inconsistent measurement of user-space systemd services, which prevents reliable remote attestation and LUKS disk decryption on affected systems.

arXiv cs.CR · 11d agoResearch

PEEP Turns Chrome and Edge Into Post-Compromise Backdoors for Host Command Execution

SOCRadar disclosed PEEP, a post-exploitation Chromium extension toolkit that turns Chrome and Edge into host-level backdoors via native messaging and C2 polling.

SOCRadar researchers detailed PEEP, a Chromium-based post-exploitation toolkit masquerading as a 'Smart Bookmarks' extension injected directly into Chrome and Edge profiles by forging Secure Preferences integrity values, bypassing Web Store checks. A native-messaging host binary (nm_host.exe) extends the browser agent to host-level command execution, file management, credential theft, and session hijacking, while the extension polls C2 endpoints at 206.237.30.232 or xfjcc.fun every 30 seconds over plaintext HTTP and exfiltrates browsing history, cookies, and tab metadata. PEEP is derived from the open-source RedExt red teaming framework, adds PowerShell persistence scripts, and includes a Linux-targeting Python script, suggesting cross-platform intent. The activity is unattributed but contains Chinese-language artifacts; a C2 /health endpoint showed 34 agent entries and 10 active sessions.

The Hacker News · 8d agoMalware in the wild

Eleethub: A Cryptocurrency Mining Botnet with Rootkit for Self

Unit 42 uncovered Eleethub, a Perl-based Bitcoin mining botnet using a crafted rootkit and libprocesshider to evade detection, still under development with few infections.

Unit 42 discovered an under-development Perl Shellbot campaign that mines Bitcoin using xmrig and emech while evading detection via a rootkit that replaces the ps tool and the LD_PRELOAD-based libprocesshider.so library. Infected devices download a malicious shell script, connect to IRC-based C2 at eleethub.com and the UnderNet network, and can receive commands for UDP/TCP floods, port scans, and HTTP attacks. The botnet can affect Unix systems and Windows 10 hosts running a Linux subsystem, and its operators use the 'Los Zetas' branding, though they are unlikely to be the Mexican drug cartel. Researchers found only a few compromised 'zombies' before the campaign expanded.

Palo Alto Unit 42 · 27d agoMalware in the wild

USN-8760-1: Linux kernel (NVIDIA) vulnerabilities

Canonical issues USN-8760-1 patching multiple Linux kernel (NVIDIA) vulnerabilities across numerous subsystems and CPU architectures.

Canonical published USN-8760-1 to correct several Linux kernel (NVIDIA) vulnerabilities that an attacker could possibly use to compromise the system. The update fixes flaws spanning UAPI, the kernel build system, ARM32, ARM64, RISC-V, S390, and x86 architectures. Patched subsystems also include the block layer, cryptographic API, Compute Acceleration Framework, Intel NPU driver, ACPI and Bluetooth drivers, and the hardware random number generator core.

Ubuntu Security Notices · 23h agoAdvisory

ZDI-26-608: Linux Kernel KVM IOAPIC Use-After-Free Local Privilege Escalation Vulnerability

The Linux kernel KVM IOAPIC has a use-after-free (CVSS 8.2) allowing local privilege escalation, but exploitation requires high-privileged code execution first.

ZDI-26-608 describes a use-after-free vulnerability in the Linux kernel's KVM IOAPIC component, with a CVSS score of 8.2. An attacker must first obtain the ability to execute high-privileged code on the target system, which limits the practical impact of the privilege escalation. The advisory text does not list an assigned CVE identifier.

ZDI Published Advisories · 23d agoVulnerability

DeepZero: Open-source hunting for vulnerable Windows drivers

DeepZero, a new open-source engine, automates discovery of exploitable Windows kernel drivers for BYOVD attacks using Ghidra, Semgrep, and an LLM.

DeepZero is a free, open-source Python pipeline orchestrator that automates hunting for exploitable Windows kernel drivers relevant to BYOVD (bring your own vulnerable driver) attacks. Its seven-stage YAML pipeline parses PE headers, filters for kernel-mode drivers with IOCTL surfaces, excludes drivers listed on loldrivers.io, then runs headless Ghidra decompilation, Semgrep scanning, and an LLM-based exploitability assessment. The maintainer reports multiple verified vulnerabilities in the Snappy Driver Installer corpus, some still in the disclosure process, and notes findings involving plug-and-play-created device objects may need physical hardware to confirm.

Help Net Security · 3h agoTools

New Ted Backdoor Hides Inside Victims' Own HAProxy Builds to Intercept Web Traffic

Rapid7 found a new backdoor, ted, compiled into trojanized HAProxy at two South Korean organizations, with medium-confidence attribution to North Korean actors.

Rapid7 documented a previously undocumented Linux toolkit named ted compiled into the HAProxy load balancer binaries of two South Korean organizations in the automotive and media sectors. The implant intercepts web traffic, serves altered pages only to filtered visitors, and hides C2 exchanges from backend logs and HAProxy statistics; a companion RAT, curlRAT, beacons on a default 12-hour schedule. The toolkit also trojanizes crond, sshd, agetty, atd, and polkitd binaries and sanitizes logs and bash history. Rapid7 attributes the activity with medium confidence to North Korean state-sponsored actors, with domain infrastructure overlapping APT37 listings in maltrail and delivery resembling the Operation SyncHole campaign.

The Hacker News · 11d agoThreat actor in the wild

ZDI-26-680: Linux Kernel Crypto Subsystem Use-After-Free Local Privilege Escalation Vulnerability

ZDI discloses a Linux kernel crypto subsystem use-after-free (CVE-2026-31719, CVSS 8.8) letting local low-privileged attackers escalate to root.

ZDI advisory ZDI-26-680 covers a use-after-free vulnerability in the Linux kernel crypto subsystem, tracked as CVE-2026-31719 with a CVSS score of 8.8. A local attacker who can already execute low-privileged code can exploit it to escalate privileges on affected installations. The advisory does not report any exploitation in the wild.

Re: Retrospective by 'gpg.fail' authors

Sam James replies to GnuPG author Werner Koch that upstream may freely adopt stricter -W compiler warnings, while distros should avoid blanket -Werror.

This is an oss-security mailing list reply by Sam James (Gentoo toolchain maintainer) to Werner Koch in the thread on the 'gpg.fail' authors' retrospective about GnuPG. James states that upstream projects like GnuPG should feel free to enable whatever -W* warning flags they need. He adds that distributions should not use -Werror indiscriminately, allowing narrow exceptions such as -Werror=format-security, and may reject warning-driven bugs that do not reflect real issues. No new CVE or vulnerability details are disclosed in this reply.

Re: Vulnerability fixes in util-linux-2.42.3

util-linux 2.42.3 includes vulnerability fixes, with a commit link shared for downstream tracking but no CVEs cited.

An oss-security post links a util-linux commit (286dd3ff41526b582ef48830de239dffbaa61f90) as part of the 2.42.3 vulnerability fix release. No CVE identifiers, flaw descriptions, or exploitation details are provided. The item is a routine open-source fix notification for downstream distributors.

oss-security · 10d agoVulnerability1

VU#718077: UEFI Shell module embedded in SPI Flash can be used to bypass Secure Boot

CERT/CC details VU#718077: UEFI Shell embedded in SPI flash lets attackers bypass Secure Boot and execute pre-boot code; patches issued.

CERT/CC's VU#718077, reported by Eclypsium researcher Stas Lyakhov, describes how a UEFI Shell embedded in SPI flash can be abused by attackers who can modify UEFI boot configuration, creating multiple boot entries that bypass controls preventing the Shell from launching under Secure Boot. The Shell's dmem and mm commands allow arbitrary physical memory read/write, letting attackers overwrite Secure Boot values and execute unauthorized pre-boot code that can persist across reboots and OS reinstalls while degrading EDR effectiveness. AMI confirmed its Aptio UEFI BDS module is affected (CVE-2026-33197), and Cisco published an advisory for a variation affecting UCS Servers and UCS-based appliances (CVE-2026-20293). Firmware patches are being rolled out through OEM and IBV BIOS build pipelines.

Any user process can escalate to root

A disclosed local privilege escalation flaw allows any user process to escalate to root on the affected system.

A Lobsters-linked security write-up describes a vulnerability in which any user process can escalate its privileges to root. The feed text provides no product name, CVE identifier, CVSS score, or exploitation details, limiting available detail. Local privilege escalation flaws are commonly chained with other issues for full system compromise, so defenders should review the full write-up for affected versions and patches.

Lobsters · security · 15d agoVulnerability

USN-8748-1: Linux kernel (NVIDIA) vulnerabilities

Ubuntu released USN-8748-1 patching multiple Linux kernel (NVIDIA) vulnerabilities across networking, file system, and crypto subsystems.

Ubuntu issued security notice USN-8748-1 fixing several Linux kernel vulnerabilities affecting the NVIDIA Tegra memory controller driver, hardware crypto device drivers, and network drivers, among others. Affected subsystems include GFS2, OCFS2, and SMB file systems, B.A.T.M.A.N. meshing, Ceph, Netfilter, Open vSwitch, IPv4/IPv6, RxRPC, SCTP, and TIPC. An attacker could potentially exploit these flaws to compromise the system.