# CVE-2025-68621: Trilium Notes has a Timing Attack Vulnerability in /api/login/sync

> Attackers can bypass authentication via timing attacks on the sync endpoint, gaining full read/write access to the victim's knowledge base.

- **Severity:** High 7.4 (`CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 6 Feb 2026
- **Updated:** 9 Feb 2026
- **Also known as:** GHSA-hxf6-58cx-qq3x

## What is CVE-2025-68621?

CVE-2025-68621 is a high-severity authentication bypass vulnerability in TriliumNext Trilium, published on 6 Feb 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Trilium Notes is an open-source, cross-platform hierarchical note taking application with focus on building large personal knowledge bases.  Prior to 0.101.0, a critical timing attack vulnerability in Trilium's sync authentication endpoint allows unauthenticated remote attackers to recover HMAC authentication hashes byte-by-byte through statistical timing analysis. This enables complete authentication bypass without password knowledge, granting full read/write access to victim's knowledge base. This vulnerability is fixed in 0.101.0.

Weakness: CWE-208 (Observable Timing Discrepancy)

## Which versions are affected by CVE-2025-68621?

It affects 1 product.


Products: Triliumnotes Trilium.

## How do I fix CVE-2025-68621?

No fix has been published for CVE-2025-68621 yet. Limit exposure of the affected software until one is available.

## Is CVE-2025-68621 being exploited?

There is no known exploitation of CVE-2025-68621 in the wild and no public exploit code.

Public exploit code:

- https://github.com/sivaadityacoder/CVE-2025-68621 (github_poc): https://github.com/sivaadityacoder/CVE-2025-68621

## Other vulnerabilities in TriliumNext Trilium

- [CVE-2026-48996](https://insights.sbomify.com/CVE-2026-48996/): Trilium: Malicious import with GeoMap marker title XSS leads to RCE on the desktop client (critical 9.3)
- [CVE-2026-53578](https://insights.sbomify.com/CVE-2026-53578/): Trilium: Note Import to RCE via Mind Elixir dangerouslySetInnerHtml (critical 9.3)
- [CVE-2026-53579](https://insights.sbomify.com/CVE-2026-53579/): Trilium: Note Import to RCE via Book Note (critical 9.3)
- [CVE-2026-47727](https://insights.sbomify.com/CVE-2026-47727/): Code injection in Trilium (high 8.6)
- [CVE-2026-53580](https://insights.sbomify.com/CVE-2026-53580/): Trilium arbitrary file read and denial of service via file:// URLs in the automatic image-download feature (high 8.1)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2025-68621 and fix it if it is affected.

What it is: CVE-2025-68621 is a high-severity authentication bypass vulnerability in TriliumNext Trilium, published on 6 Feb 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2025-68621 in the wild and no public exploit code.

Affected product: TriliumNext Trilium. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2025-68621/ (Markdown: https://insights.sbomify.com/CVE-2025-68621/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-68621
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-68621
- OSV: https://osv.dev/vulnerability/CVE-2025-68621

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-68621/
Summaries are generated and may contain mistakes; the official description above is the record.