# CVE-2026-58520: UrlShortener defaults to ineffective validation open to third-party redirects

> Attackers can exploit weak validation in the UrlShortener extension to redirect users to malicious third-party sites.

- **Severity:** Medium 6.9 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:L/SC:L/SI:L/SA:L`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 1 Jul 2026
- **Updated:** 1 Jul 2026
- **Also known as:** GHSA-q84p-w2wj-782m, MINI-5qpm-hr62-pw2p, MINI-ccr3-89p3-5346, MINI-xmf3-4v5f-25gj

## What is CVE-2026-58520?

CVE-2026-58520 is a medium-severity vulnerability in Mediawiki Mediawiki, published on 1 Jul 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

URL redirection to untrusted site ('open redirect') vulnerability in The Wikimedia Foundation Mediawiki - UrlShortener Extension allows Cross-Site Flashing.

This issue affects Mediawiki - UrlShortener Extension: from * before 1.43.9, 1.44.6, 1.45.4.

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

## Which versions are affected by CVE-2026-58520?

It affects 1 product.


Products: Mediawiki Mediawiki.

## How do I fix CVE-2026-58520?

Upgrade to a fixed version.

## Is CVE-2026-58520 being exploited?

There is no known exploitation of CVE-2026-58520 in the wild and no public exploit code.

## Other vulnerabilities in Mediawiki Mediawiki

- [CVE-2023-37303](https://insights.sbomify.com/CVE-2023-37303/): Denial of service in n/a (critical 9.8)
- [CVE-2022-29904](https://insights.sbomify.com/CVE-2022-29904/): SQL injection in n/a (critical 9.8)
- [CVE-2022-29906](https://insights.sbomify.com/CVE-2022-29906/): Missing authorization in n/a (critical 9.8)
- [CVE-2022-28205](https://insights.sbomify.com/CVE-2022-28205/): Business logic in n/a (critical 9.8)
- [CVE-2022-28206](https://insights.sbomify.com/CVE-2022-28206/): Missing authorization in n/a (critical 9.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-58520 and fix it if it is affected.

What it is: CVE-2026-58520 is a medium-severity vulnerability in Mediawiki Mediawiki, published on 1 Jul 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-2026-58520 in the wild and no public exploit code.

Affected product: Mediawiki Mediawiki. 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-2026-58520/ (Markdown: https://insights.sbomify.com/CVE-2026-58520/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-58520
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-58520
- OSV: https://osv.dev/vulnerability/CVE-2026-58520

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-58520/
Summaries are generated and may contain mistakes; the official description above is the record.