# CVE-2026-40905: LinkAce: Password Reset Poisoning via X-Forwarded-Host Header Injection Leading to Account Takeover

> Attackers can hijack password reset links via X-Forwarded-Host injection to steal tokens and take over user accounts.

- **Severity:** High 8.1 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:R/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:** A user has to click or open something
- **Fix available:** No
- **Published:** 21 Apr 2026
- **Updated:** 21 Apr 2026
- **Also known as:** GHSA-48wv-jpf4-vjfv

## What is CVE-2026-40905?

CVE-2026-40905 is a high-severity vulnerability in Kovah LinkAce, published on 21 Apr 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.

### Official description

LinkAce is a self-hosted archive to collect website links. Prior to 2.5.4, a password reset poisoning vulnerability was identified in the application due to improper trust of user-controlled HTTP headers. The application uses the X-Forwarded-Host header when generating password reset URLs. By manipulating this header during a password reset request, an attacker can inject an attacker-controlled domain into the reset link sent via email. As a result, the victim receives a password reset email containing a malicious link pointing to an attacker-controlled domain. When the victim clicks the link, the password reset token is transmitted to the attacker-controlled server. An attacker can capture this token and use it to reset the victim’s password, leading to full account takeover. This vulnerability is fixed in 2.5.4.

Weakness: CWE-601 (URL Redirection to Untrusted Site)

## Which versions are affected by CVE-2026-40905?


## How do I fix CVE-2026-40905?

No fix has been published for CVE-2026-40905 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-40905 being exploited?

There is no known exploitation of CVE-2026-40905 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-40905 and fix it if it is affected.

What it is: CVE-2026-40905 is a high-severity vulnerability in Kovah LinkAce, published on 21 Apr 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Exploitation: There is no known exploitation of CVE-2026-40905 in the wild and no public exploit code.

Affected product: Kovah LinkAce. 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-2026-40905/ (Markdown: https://insights.sbomify.com/CVE-2026-40905/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-40905
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-40905
- OSV: https://osv.dev/vulnerability/CVE-2026-40905

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-40905/
Summaries are generated and may contain mistakes; the official description above is the record.