# CVE-2026-18737: Shlink Blind SQL Injection via tags/stats orderBy Parameter

> Authenticated attackers can extract sensitive tenant data via blind SQL injection in the tag statistics endpoint of Shlink.

- **Severity:** High 7.1 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 3 Aug 2026
- **Updated:** 5 Aug 2026
- **Also known as:** GHSA-2jhc-j623-f52p

## What is CVE-2026-18737?

CVE-2026-18737 is a high-severity SQL injection vulnerability in shlinkio Shlink, published on 3 Aug 2026. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

Shlink contains a blind SQL injection vulnerability that allows any authenticated API key holder to inject arbitrary SQL fragments by supplying an unvalidated direction value in the orderBy query parameter of the tag statistics endpoint. Attackers can craft a malicious direction string containing SQL subqueries that flows unsanitized into a Doctrine QueryBuilder ORDER BY clause, enabling time-based, boolean-oracle, and error-based extraction of sensitive data including long URLs, visitor records, IP addresses, geolocation data, user agents, and hashed API key secrets from any tenant.

Weakness: CWE-89 (Improper Neutralization of Special Elements used in an SQL Command)

## Which versions are affected by CVE-2026-18737?


## How do I fix CVE-2026-18737?

No fix has been published for CVE-2026-18737 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-18737 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-18737 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-18737 and fix it if it is affected.

What it is: CVE-2026-18737 is a high-severity SQL injection vulnerability in shlinkio Shlink, published on 3 Aug 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-18737 exists.

Affected product: shlinkio Shlink. 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-2026-18737/ (Markdown: https://insights.sbomify.com/CVE-2026-18737/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-18737
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-18737
- OSV: https://osv.dev/vulnerability/CVE-2026-18737

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From sbomify Insights: https://insights.sbomify.com/CVE-2026-18737/
Summaries are generated and may contain mistakes; the official description above is the record.