CVE-2026-47899: Arbitrary File Read, Write, Rename, and Delete in Logseq

Synopsis

An arbitrary file read, write, rename, and delete vulnerability exists in Logseq's Electron preload script. The vulnerability is reachable locally without authentication: any JavaScript executing inside the renderer process (for example via a cross-site scripting payload or a malicious plugin) can invoke unvalidated IPC handlers to reach the host filesystem. Successful exploitation gives an attacker full read and write access to arbitrary files on the user's system, as well as the ability to modify or delete files in other security contexts. No fix version has been published; HarborGuard tracks the upstream advisory and will make a patched-image rebuild available as soon as a fix is released.

HarborGuard Coverage

Exploit Conditions

• Network reachabilityNot required

  The attacker needs an existing shell or process on the host, or the ability to execute JavaScript inside the Logseq renderer (for example through a plugin or XSS); no network-level access to the service is required.

• AuthenticationNot required

  No credentials or account privileges are required; any JavaScript execution context inside the renderer is sufficient to invoke the vulnerable IPC handlers.

• Victim interactionNot required

  No victim interaction is required once the attacker has JavaScript execution in the renderer; the IPC call is made programmatically without any user gesture.

• Attack complexityDetail

  Attack complexity is low in terms of exploit mechanics, though AT:P indicates that specific target conditions (such as a loaded plugin or an XSS entry point) must be present in the environment.

Blast Radius

• Reads arbitrary files from the user's filesystem, including credentials, private keys, configuration files, and documents stored anywhere the OS user account can access.
• Writes or overwrites arbitrary files, enabling an attacker to plant malicious content, replace binaries, or corrupt application data.
• Modifies or deletes files in other security contexts beyond the Logseq application itself, potentially affecting system integrity outside the app boundary.
• Affects both the local security context and subsequent security contexts (SC:H, SI:H), meaning damage can propagate to data or processes that depend on the tampered files.