ZeroHour

Search: “local”

878 stories

Microsoft Patch Tuesday, September 2026 Security Update Review

Microsoft's September 2026 Patch Tuesday fixes 974 vulnerabilities, including 113 critical and two actively exploited Windows privilege escalation flaws.

Microsoft's September 2026 Patch Tuesday fixes 974 vulnerabilities, its largest release ever, including 113 critical and 860 important, covering Windows HTTP.sys, Hyper-V, Entra ID, Exchange Server, Office, DNS, and more. Two zero-days are confirmed exploited in the wild: CVE-2026-81963 (Windows Update Stack EoP) and CVE-2026-85880 (ALPC heap overflow), both letting authenticated attackers gain SYSTEM privileges. Notable criticals include an Entra ID authentication bypass (CVE-2026-62916) and multiple Windows DNS Server and Office remote code execution flaws.

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 · 21h agofirst · 22h agoVulnerability 4 sourcesCVE-2026-90894

Six new dnsmasq vulnerabilities open the door to DNS cache poisoning, local root

Six dnsmasq flaws enable DNS cache poisoning, DoS, memory leaks, and local root code execution; fixes ship in version 2.92rel2.

Researchers disclosed six dnsmasq vulnerabilities spanning memory safety and input validation, including heap buffer overflows in extract_name() and extract_addresses(), DNSSEC infinite-loop and out-of-bounds read flaws, and a DHCPv6 out-of-bounds write allowing local root code execution. Exploitation paths include DNS cache poisoning, bypassing security controls, remote denial of service, and local privilege escalation. Maintainers released version 2.92rel2 with fixes, and a stable 2.93 release is expected within weeks.

VU#687587: AOMEI Backupper amwrtdrv.sys local privilege escalation vulnerability allows arbitrary writes to physical disks

AOMEI Backupper 8.4.0 driver flaw CVE-2026-12780 lets unprivileged users write physical disks and execute UEFI code, bypassing HVCI and EDR.

CERT/CC issued VU#687587 for CVE-2026-12780, an incorrect permission assignment (CWE-732) in the amwrtdrv.sys kernel driver shipped with AOMEI Backupper 8.4.0. The driver exposes a world-accessible device object without a security descriptor, allowing any unprivileged user to write arbitrary physical disk sectors; with Secure Boot disabled, an attacker can modify the GPT and inject a UEFI payload that executes before the OS loads, bypassing HVCI, EDR, Windows Defender and Hyper-V isolation. On TPM-only BitLocker configurations the attack can capture Volume Master Key material during pre-boot. AOMEI has shipped patches; users who cannot update should uninstall the software or disable the amwrtdrv.sys service, and enabling Secure Boot adds defense in depth.

The skb that wasn't freed - the Fragnesia primitive via Open vSwitch

Doyensec details CVE-2026-90049 in Open vSwitch, enabling deterministic Linux kernel local privilege escalation on default major distribution installs.

Doyensec reports that the Open vSwitch datapath strips the SKBFL_SHARED_FRAG flag from packets it is still forwarding, allowing an in-place decrypt to write attacker-chosen bytes into root-owned page cache — a Dirty COW-class primitive that re-opens the Fragnesia bug family. The issues are tracked as CVE-2026-90049, CVE-2026-89487, and CVE-2026-80977, and were reported to the kernel security team with fixes coordinated alongside OVS maintainers. A deterministic local privilege escalation works on default installs of Arch, Fedora, Debian, Amazon Linux, and RHEL where unprivileged user namespaces and openvswitch auto-loading are enabled; the fix landed in mainline and shipped in stable on 09/04/2026. The write technique builds on the earlier Fragnesia and Dirty Frag bugs, including CVE-2026-43284 and CVE-2026-43500.

The Apple Security Update Review for September 2026

Apple's September 2026 updates patch 45+ flaws, including a 9.8 Screen Sharing authentication bypass (CVE-2026-65400) already listed in CISA's KEV.

ZDI's review of Apple's September 2026 security updates catalogs dozens of CVEs across macOS, iOS, iPadOS, watchOS and other platforms. CVE-2026-65400 (CVSS 9.8) lets a network attacker authenticate to Screen Sharing Server without valid credentials and is flagged as KEV, while CVE-2026-65414 (CVSS 9.8) enables remote code execution via Bluetooth. The set also includes 8.8-rated memory corruption flaws in WebKit, WebRTC, CUPS, ImageIO and the kernel, plus sandbox escapes, privilege escalations to root, and arbitrary code execution via crafted files.