Security readout for executives and security teams
Plain-English summary
Werkzeug before 0.11.6 could mishandle URLs with a double slash and redirect users to an unintended external destination. This is not described as remote code execution or data theft, but it can help phishing or trust-abuse campaigns when exposed in public web apps.
Executive priority
Treat this as a targeted web trust issue, not a platform-wide emergency. Prioritize internet-facing applications, login flows, and customer-facing links that may use old Werkzeug versions.
Technical view
The source record describes an open redirect in Werkzeug versions before 0.11.6 caused by double-slash URL handling. Public references point to Pallets Flask and Werkzeug issue discussions and a Werkzeug pull request. No CVSS, CWE, affected CPEs, or active exploitation evidence is provided in the bundle.
Likely exposure
Exposure is most likely in Python web applications that depend on Werkzeug before 0.11.6 and perform redirects using affected URL handling. Flask-based applications may be relevant only where they use the vulnerable Werkzeug version.
Exploitation context
The bundle does not cite active exploitation, and this CVE is not marked KEV. The practical risk is redirecting users from a trusted application domain to an attacker-chosen destination, supporting phishing or authentication-flow confusion.
Researcher notes
Evidence is sparse: the CVE description names Werkzeug before 0.11.6 and double-slash URL handling, but the bundle lacks CVSS, CWE, CPEs, and exploit-status details. Keep conclusions tied to Pallets issue and pull-request references.
Mitigation direction
- Upgrade Werkzeug to 0.11.6 or later where applicable.
- Check Pallets/Werkzeug guidance for any application-specific remediation details.
- Review application redirects for strict destination allowlisting.
- Avoid trusting user-controlled redirect destinations without validation.
Validation and detection
- Inventory dependency manifests and lockfiles for Werkzeug versions before 0.11.6.
- Identify public routes that perform redirects or accept redirect destination parameters.
- Confirm redirect validation rejects unintended external destinations.
- Verify fixed services run the expected Werkzeug version after deployment.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CVE-2020-28724 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- Unknown
- CVSS
- Not scored
- Known Exploited
- No
- Published
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CVSS and timeline data
No CVSS vectors or timeline events were available in the normalized CVE source material.
Source materials
- CVE List V5 sourceCVE List V5
- https://github.com/pallets/flask/issues/1639CVE reference · x_refsource_MISC
- https://github.com/pallets/werkzeug/issues/822CVE reference · x_refsource_MISC
- https://github.com/pallets/werkzeug/pull/890/filesCVE reference · x_refsource_MISC
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.