# CVE-2026-73849: emlog allows unauthenticated reinstallation via `install.php?action=reinstall`.

> Unauthenticated attackers can reinstall Emlog to overwrite configuration and create a new administrator account, leading to full site takeover.

- **Severity:** Critical 9.8 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 14 Aug 2026
- **Updated:** 18 Aug 2026
- **Also known as:** GHSA-v5qq-p8mp-3gxm

## What is CVE-2026-73849?

CVE-2026-73849 is a critical missing authorization vulnerability in emlog, published on 14 Aug 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Emlog is an open source website building system. In 2.6.26 and earlier, install.php accepts action=reinstall without authentication and deliberately skips the already-installed check because the guard runs only when $act != 'reinstall'. A remote attacker can submit hostname, dbuser, dbpasswd, dbname, dbprefix, username, password, and email values to cause file_put_contents('config.php', $config) to overwrite the configuration with attacker-controlled database settings and create a new administrator account. No fixed version is available as of this review.

Weakness: CWE-306 (Missing Authentication for Critical Functionality)

## Which versions are affected by CVE-2026-73849?


## How do I fix CVE-2026-73849?

No fix has been published for CVE-2026-73849 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-73849 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-73849 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-73849 and fix it if it is affected.

What it is: CVE-2026-73849 is a critical missing authorization vulnerability in emlog, published on 14 Aug 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-73849 exists.

Affected product: emlog. 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-2026-73849/ (Markdown: https://insights.sbomify.com/CVE-2026-73849/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-73849
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-73849
- OSV: https://osv.dev/vulnerability/CVE-2026-73849

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-73849/
Summaries are generated and may contain mistakes; the official description above is the record.