CVE-2026-90954: the affected product Security Vulnerability (CVSS 7.8)

Cursor is a code editor built for programming with AI. Prior to 3.0, Cursor runs agent terminal commands in a sandbox by default. Before a Write, the agent canonicalizes the target path to confirm it stays inside the workspace, but when canonicalization fails it falls back to the original path and writes without approval. A malicious agent can create an in-workspace symlink that points outside the workspace and force canonicalization to fail — either because the target does not exist or because read permission is removed from the path — so the agent writes through the symlink to an arbitrary location without approval. A malicious agent could write arbitrary files outside the workspace under the user's privileges. This enables non-sandboxed Remote Code Execution — for example by overwriting the cursorsandbox helper so later commands run unsandboxed — with no user interaction beyond a benign prompt. This vulnerability is fixed in 3.0.

Flatpak is a Linux application sandboxing and distribution framework. Prior to 1.16.4, the Flatpak portal accepts paths in the sandbox-expose options which can be app-controlled symlinks pointing at arbitrary paths. Flatpak run mounts the resolved host path in the sandbox. This gives apps access to all host files and can be used as a primitive to gain code execution in the host context. This vulnerability is fixed in 1.16.4.

A link following vulnerability has been reported to affect several QNAP operating system versions. The remote attackers can then exploit the vulnerability to traverse the file system to unintended locations. We have already fixed the vulnerability in the following versions: QTS 5.2.8.3350 build 20251216 and later QuTS hero h5.3.2.3354 build 20251225 and later QuTS hero h5.2.8.3350 build 20251216 and later

Archive::Tar versions before 3.08 for Perl extract symlinks with attacker controlled targets outside the extraction directory. _make_special_file() passes the tar header's linkname to symlink() without validating it against absolute paths or .. segments. The secure-extract mode check that guards regular file extraction does not cover the symlink target. A subsequent open through the extracted name reads or writes the attacker chosen path.

Dokku is a docker-powered PaaS. Prior to 0.38.2, the git:from-archive and certs:add commands extract user-supplied tar/zip archives into temporary directories without sanitizing member paths or preventing symlink traversal. GNU tar creates symlinks during extraction and follows them for subsequent entries, allowing an attacker to write arbitrary files anywhere writable by the dokku user — including overwriting ~/.ssh/authorized_keys to gain unrestricted shell access. This vulnerability is fixed in 0.38.2.

Himmelblau is an interoperability suite for Microsoft Azure Entra ID and Intune. Prior to 3.1.0 and 2.3.8, the himmelblaud-tasks daemon, running as root, writes Kerberos cache files under /tmp/krb5cc_<uid> without symlink protections. Since commit 87a51ee, PrivateTmp is explicitly removed from the tasks daemon's systemd hardening, exposing it to the host /tmp. A local user can exploit this via symlink attacks to chown or overwrite arbitrary files, achieving local privilege escalation. This vulnerability is fixed in 3.1.0 and 2.3.8.