CVE-2026-39309

CVE-2026-39309 is a medium-severity vulnerability with a CVSS 3.x base score of 5.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-290.

Key facts

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.

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.
How severe is CVE-2026-39309?
CVE-2026-39309 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2026-39309 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (7th percentile), an estimate of the probability of exploitation in the next 30 days.
How do I fix CVE-2026-39309?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-39309 have an EU (EUVD) identifier?
Yes. CVE-2026-39309 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-31008.
When was CVE-2026-39309 published?
CVE-2026-39309 was published on 2026-05-20 and last updated on 2026-06-17.

References

Other CWE-290 vulnerabilities

Browse all CWE-290 vulnerabilities →