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8 stories in the last 3d

Microsoft Releases Emergency Windows 11 Update Following Patch Tuesday Bugs

Microsoft issued emergency Windows 11 update KB5129195 to fix Patch Tuesday regressions and fully close the CVE-2026-62721 privilege escalation flaw.

Microsoft shipped out-of-band cumulative update KB5129195 for Windows 11 24H2 and 25H2 (builds 26100.9457 and 26200.9457) after the September 8 Patch Tuesday rollup, which addressed over 960 CVEs including two actively exploited flaws, broke Remote Desktop Services, Hyper-V Plan9 folder sharing, and USB audio. The emergency release also strengthens the incomplete fix for CVE-2026-62721, an elevation-of-privilege flaw in the Windows User-Mode Power Service that could let a local attacker gain SYSTEM privileges. Companion patches cover Windows 11 26H1, Windows 10, and Windows Server. Some USB Audio Class 1.0 and AMD Radeon graphics issues remain unresolved.

Cyber Security News · 15h agoVulnerability in the wildCVE-2026-62721

CVE-2026-89775: Guest-to-Host Escape in KVM/arm64

Disclosed CVE-2026-89775 lets a guest VM escape to the host on KVM/arm64 systems with nested virtualization enabled.

Researcher Hyunwoo Kim disclosed CVE-2026-89775, a guest-to-host escape in KVM/arm64, after the embargo agreed with linux-distros maintainers expired. The root cause is a type truncation of the stage-1 walk level that makes a size computation return 0, the value meaning 'size unknown'. The VNCR pseudo-TLB invalidation path then interprets that 0 as a valid value on ARM64 hosts where nested virtualization is enabled.

Parallels Desktop flaw hands any local user root on a Mac (CVE-2026-90894)

CVE-2026-90894 in Parallels Desktop for Mac lets any local user gain root via argument injection; patched in v27.0.0, PoC withheld.

JFrog researchers disclosed CVE-2026-90894, an argument injection flaw in Parallels Desktop for Mac v26.4.0 on Apple silicon that lets any local user gain root on the host. The chain combines a world-writable Unix socket for prl_disp_service (which runs as root), weak peer-credential authentication, and argument injection via --use-compress-program in the appliance extraction tar path. Alludo fixed the flaw in Parallels Desktop v27.0.0 in early September 2026; JFrog published technical details but withheld its proof-of-concept script.

Help Net Securityupdated · 10h agofirst · 10h agoVulnerability 4 sourcesCVE-2026-90894

cPanel LiteSpeed Web Server Vulnerability Allows Shared Server Users to Gain Root-Level Access

Critical LiteSpeed Enterprise flaw fixed in 6.3.7 lets low-privilege shared-hosting users escalate to root and bypass CageFS.

cPanel issued an urgent advisory for a critical privilege escalation in LiteSpeed Web Server Enterprise versions before 6.3.7, allowing a low-privilege shared-hosting account to gain root-level server control and bypass tenant isolation controls including CloudLinux CageFS. Root access would let attackers access other hosted sites, steal databases and credentials, deploy phishing pages, and install backdoors. Administrators are urged to upgrade to 6.3.7 immediately via lsup.sh and to review privileged account activity, cron jobs, SSH keys, and system binaries; no CVE identifier was published.

Cyber Security News · 1d agoVulnerability

Windows 11 KB5124008 update breaks domain trust for some users

Microsoft is investigating Windows 11 KB5124008 breaking Active Directory domain trust, leaving some users unable to log in with valid credentials.

Administrators report the Windows 11 KB5124008 security update breaks the secure channel between domain-joined machines and Active Directory, causing login failures on Windows 11 25H2 systems after reboot. The failures are linked to the Machine Identity Isolation feature, which in enforcement mode moves machine account secrets into Credential Guard and removes the LSA copy; one admin saw 11 of roughly 256 devices affected. Workarounds include setting MachineIdentityIsolation to 0 and repairing the secure channel with Test-ComputerSecureChannel, though Microsoft has confirmed no root cause or official fix and warns disabling the feature can also break domain authentication.

BleepingComputer · 2h agoVulnerability

Oracle September 2026 Critical Security Patch Update addresses 672 CVEs

Oracle's September 2026 CSPU fixes 672 CVEs across 673 patches, including 104 critical updates, with E-Business Suite receiving the most patches (159).

Oracle released its September 2026 Critical Security Patch Update fixing 672 unique CVEs via 673 security updates across 17 product families, with 104 patches (15.5%) rated critical and 503 rated high. Oracle E-Business Suite received the most patches at 159 (23.6%), followed by Fusion Middleware at 153, of which 78 are remotely exploitable without authentication. The CSPU is a monthly release cycle Oracle introduced in May 2026 between larger quarterly CPUs. Tenable will publish plugins to identify affected systems.

Tenable Blog · 1d agoVulnerability

$1 Million Sandbox Challenge Uncovers Linux Kernel Flaws

Vercel's $1M sandbox challenge surfaced two Linux kernel networking defects—one leaking host kernel memory, one crashing hosts—with CVEs pending.

Vercel ran a two-week, $1 million sandbox escape challenge (Aug 18–Sep 1) on its Firecracker-based microVM sandbox, receiving 1,285 reports and committing ~$325k in payouts (1 Critical, 7 High, 15 Medium, 49 Low validated so far). No attacker accessed real customer data. The most important filing found two independent Linux kernel networking stack defects—one leaks host kernel memory, the other deterministically crashes the host—with wide implications for cloud providers isolating workloads via the same kernel layer. Fixes are under private review with CVEs pending; Vercel also plans to open-source its agentic report-triage agent built on the Eve framework running Kimi K3.

SecurityWeek · 1d agoVulnerability2

AWS Systems Manager Agent Vulnerability Allows Attackers to Bypass Port-Forwarding Restrictions

Critical SSRF flaw in AWS SSM Agent (CVE-2026-89049) lets authenticated users bypass link-local denylists and reach EC2 Instance Metadata Service for IAM credentials.

CVE-2026-89049 (Critical, CVSS v3.1 AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H) affects Amazon SSM Agent versions earlier than 3.3.4851.0, with the fix shipping in 3.3.4851.0. The remote-host port-forwarding feature's denylist for link-local addresses can be bypassed because equivalent address representations are not validated, enabling SSRF to restricted endpoints such as the EC2 Instance Metadata Service at 169.254.169.254. An attacker with authenticated AWS access and ssm:StartSession permission could retrieve instance profile IAM credentials and pivot to S3, Secrets Manager, Lambda, or other cloud resources depending on role permissions.