# CVE-2021-32806: URL Redirection to Untrusted Site ('Open Redirect') in Products.isurlinportal

> Attackers can redirect victims to malicious sites via flawed URL validation, facilitating phishing attacks against Plone users.

- **Severity:** Medium 6.5 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/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:** Yes
- **Published:** 2 Aug 2021
- **Updated:** 3 Aug 2024
- **Also known as:** GHSA-q3m9-9fj2-mfwr, PYSEC-2021-323

## What is CVE-2021-32806?

CVE-2021-32806 is a medium-severity vulnerability in plone Products.isurlinportal, published on 2 Aug 2021. 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

Products.isurlinportal is a replacement for isURLInPortal method in Plone. Versions of Products.isurlinportal prior to 1.2.0 have an Open Redirect vulnerability. Various parts of Plone use the 'is url in portal' check for security, mostly to see if it is safe to redirect to a url. A url like `https://example.org` is not in the portal. The url `https:example.org` without slashes is considered to be in the portal. When redirecting, some browsers go to `https://example.org`, others give an error. Attackers may use this to redirect victims to their site, especially as part of a phishing attack. The problem has been patched in Products.isurlinportal 1.2.0.

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

## Which versions are affected by CVE-2021-32806?

3 open source packages ship an affected version, including Products.isurlinportal and products-isurlinportal. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `Products.isurlinportal` | PyPI | All versions | 1.2.0 |
| `products-isurlinportal` | PyPI | All versions | 1.2.0 |
| `products-isurlinportal` | PyPI | All versions | 1.2.0 |

Products: Plone Isurlinportal.

## How do I fix CVE-2021-32806?

Upgrade Products.isurlinportal to 1.2.0 or later.

## Is CVE-2021-32806 being exploited?

There is no known exploitation of CVE-2021-32806 in the wild and no public exploit code.

## Other vulnerabilities in plone Products.isurlinportal

- [CVE-2026-28413](https://insights.sbomify.com/CVE-2026-28413/): Products.isurlinportal: Possible open redirect when using more than 2 forward slashes (medium 5.3)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-32806 and fix it if it is affected.

What it is: CVE-2021-32806 is a medium-severity vulnerability in plone Products.isurlinportal, published on 2 Aug 2021. 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-2021-32806 in the wild and no public exploit code.

Affected packages and fixed versions:
- Products.isurlinportal (PyPI): affected all versions; fixed in 1.2.0
- products-isurlinportal (PyPI): affected all versions; fixed in 1.2.0
- products-isurlinportal (PyPI): affected all versions; fixed in 1.2.0

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-2021-32806/ (Markdown: https://insights.sbomify.com/CVE-2021-32806/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-32806
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-32806
- OSV: https://osv.dev/vulnerability/CVE-2021-32806

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-32806/
Summaries are generated and may contain mistakes; the official description above is the record.