CVE-2026-39309

MEDIUM
Published May 20, 2026 Modified May 20, 2026 CWE-290 CWE-451

Description

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 v3.1 Score

5.5
MEDIUM
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N

EPSS — Exploit Prediction

0.0001
Probability of exploitation
0.00%
Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

Weakness Type (CWE)

CWE-290 CWE-290
CWE-451 CWE-451

References

Frequently Asked Questions

What 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. It has a CVSS v3.1 base score of 5.5 (MEDIUM).
How severe is CVE-2026-39309? +
CVE-2026-39309 has a CVSS v3.1 score of 5.5 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance. The EPSS score is 0.0001, placing it in the 0th percentile for exploitation probability.
How do I check if I'm vulnerable to CVE-2026-39309? +
You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

Related Vulnerabilities

Don't wait for an exploit

Scan your website for vulnerabilities like CVE-2026-39309 — free, no signup required.

Start Free Scan