Quick answers
- Is CVE-2020-28724 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2020-28724 being exploited in the wild.
- How severe is CVE-2020-28724?
- Low severity, with a CVSS score of 3.1, published 18 November 2020.
- Which products and versions are affected?
- werkzeug (PyPI) ECOSYSTEM:introduced=0,fixed=0.11.6.
- Is there a fix for CVE-2020-28724?
- Yes. werkzeug (PyPI): upgrade to 0.11.6 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
- How is CVE-2020-28724 attacked?
- It is attacked over the network.
- Am I affected by CVE-2020-28724?
- Check whether you run werkzeug (PyPI) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
How to fix
- werkzeug (PyPI): upgrade to 0.11.6 or later
pip install "werkzeug>=0.11.6"
Technical details
This is an open redirect vulnerability (CWE-601) in Werkzeug's URL processing logic. The vulnerability occurs when a URL path begins with a double slash (//), which is processed incorrectly by the URL routing and redirect handling code, allowing an attacker to specify an arbitrary redirect destination. The attack requires user interaction (the victim must click the crafted link) but no authentication, and is network-accessible via HTTP requests. An attacker can craft a URL like "http://trusted-app.com//../www.attacker.com" to redirect users to attacker-controlled sites. The vulnerability was fixed in version 0.11.6 and later.
Affected products
- Pallets Werkzeug before 0.11.6
Identifiers
- CVE-2020-28724
- GHSA-3p3h-qghp-hvh2
- PYSEC-2020-157
Timeline
- 2021-04-20: disclosed
- 0.11.6: patched