CVE-2026-39309
MediumWhat is CVE-2026-39309?
Trilium Notes is a cross-platform, hierarchical note taking application focused on building large personal knowledge bases. In versions 0.102.1 and prior, the Electron configuration is vulnerable to TCC Bypass via Prompt Spoofing, allowing local attackers to trigger misleading macOS permission prompts by running malicious code under the identity of the trusted app. The root cause is that the RunAsNode fuse allows launching the app in a special Node.js mode using -e to execute arbitrary system commands with Trilium Notes's permissions and identity. An attacker can leverage this through a subprocess to request any sensitive permissions, such as access to hardware (camera, microphone) and TCC-protected files, causing the TCC system prompt to appear as if the request came from Trilium rather than the attacker's code, because macOS treats the subprocess as part of the parent application. Exploitation allows access to TCC-protected resources like the screen, camera, microphone, and folders such as ~/Documents and ~/Downloads, undermining macOS's security model and UI integrity through social engineering. This issue has been fixed in version 0.102.2.
CVSS Vector Breakdown
CVSS 3.1Requires local access — attacker must be logged in or have physical access to the device.
No special conditions required. Exploit can be performed reliably and repeatedly.
No authentication required. Any anonymous user can exploit this vulnerability.
Victim must take an action (e.g. click a link, open a file) for the exploit to succeed.
Exploiting the vulnerability only affects the vulnerable component itself.
Complete loss of confidentiality. All data on the component may be exposed.
No integrity impact. Data cannot be modified.
No availability impact. Service remains fully operational.
FAQ
CVE-2026-39309 has a CVSS score of 5.5/10, rated as Medium. Review the affected products list and apply vendor patches.
CVSS (Common Vulnerability Scoring System) rates vulnerability severity from 0.0 to 10.0. CVE-2026-39309 scores 5.5/10 (Medium). Scores 9.0–10.0 are Critical, 7.0–8.9 are High, 4.0–6.9 are Medium, and below 4.0 are Low.
The list of devices confirmed to be affected by CVE-2026-39309 is shown in the "Affected Devices" section above. Check your firmware version against the vendor security advisory and apply the latest patch.
Apply the latest firmware or software update from the vendor. Check the References section above for official advisories and patch notes. If no patch is available, consider disabling the affected feature or isolating the device from untrusted networks.