# CVE-2026-19900: LB-LINK X-PRO shadow hard-coded credentials

> Hard-coded credentials in the shadow file allow remote attackers to gain privileged access to LB-LINK X-PRO devices.

- **Severity:** Critical 9.2 (`CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:P`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 15 Aug 2026
- **Updated:** 17 Aug 2026
- **Also known as:** GHSA-6pw8-xc67-fhhg

## What is CVE-2026-19900?

CVE-2026-19900 is a critical vulnerability in LB-LINK X-PRO, published on 15 Aug 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

A vulnerability was identified in LB-LINK X-PRO 1.0.22-20231206. The impacted element is an unknown function of the file /etc/shadow. The manipulation leads to hard-coded credentials. It is possible to initiate the attack remotely. A high degree of complexity is needed for the attack. The exploitability is regarded as difficult. The exploit is publicly available and might be used. The vendor was contacted early about this disclosure but did not respond in any way.

Weakness: CWE-798 (Use of Hard-coded Credentials), CWE-259 (Use of Hard-coded Password)

## Which versions are affected by CVE-2026-19900?


## How do I fix CVE-2026-19900?

No fix has been published for CVE-2026-19900 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-19900 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-19900 exists.

Public exploit code:

- cve-2026-19900-PoC (github_poc): https://github.com/on3sk-0x1/cve-2026-19900-PoC
- LB-LINK Routers - Unauthenticated Command Injection (nuclei): http/cves/2026/CVE-2026-19900.yaml

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-19900 and fix it if it is affected.

What it is: CVE-2026-19900 is a critical vulnerability in LB-LINK X-PRO, published on 15 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-2026-19900 exists.

Affected product: LB-LINK X-PRO. 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-2026-19900/ (Markdown: https://insights.sbomify.com/CVE-2026-19900/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-19900
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-19900
- OSV: https://osv.dev/vulnerability/CVE-2026-19900

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-19900/
Summaries are generated and may contain mistakes; the official description above is the record.