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.
China-Made ZBT Routers Ship With Two Implants Giving Unauthenticated Attackers Root Access
VulnCheck discloses two factory implants, SPEAKINGSTONE and DARKLANTERN, in ZBT router firmware granting unauthenticated remote attackers root command execution.
VulnCheck found two previously undocumented implants in firmware from Shenzhen Zhibotong Electronics (ZBT), tracked as CVE-2026-74232 (SPEAKINGSTONE) and CVE-2026-74233 (DARKLANTERN), each rated 9.8 on CVSS 3.1. SPEAKINGSTONE (yunmgrd) beacons to a hardcoded C2 over UDP port 10000 and supports root command execution, PPPoE credential exfiltration, DNS hijacking, and reverse SSH tunnels; DARKLANTERN (infosrvd) listens on UDP port 9992 with weak hardcoded authentication. Scanning found 203 internet-facing DARKLANTERN instances across 22 countries, and 392 devices reported to the SPEAKINGSTONE backup C2, nearly all in China on China Mobile. No fixed firmware release is named, and ZBT's white-labeling means model number rather than brand is the reliable detection check.
Malicious .git Configs Can Make Claude, Codex, Cursor, and Other AI Agents Run Attacker Code
Malicious .git core.fsmonitor configs let attacker code run in AI coding agents like Claude Code and Codex; four of eight flaws remain unpatched.
Manifold Security disclosed eight flaws across seven command-line AI coding agents where a repository's Git core.fsmonitor configuration causes agent-spawned commands to execute attacker code outside the sandbox and without approval prompts. Fixes shipped for goose (CVE-2026-72718, CVSS 4.0 score 7.0), Claude Code on one path, and Cursor, while Hermes Agent, Qwen Code, Grok Build, and a second Claude Code path were still unpatched as of September 1. OpenAI issued three CVEs for the same class in Codex, including CVE-2026-19592, and prior related bugs include CVE-2021-43891 in Visual Studio Code and CVE-2022-24346 in JetBrains IDEs. Exploitation requires the repository to arrive with its .git directory intact, such as via archives, shared drives, or USB sticks rather than an ordinary clone.