CVE-2021-32806
URL Redirection to Untrusted Site ('Open Redirect') in Products.isurlinportal
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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- Required
What an attacker can affect
- Confidentiality
- None
- Integrity
- High
- Availability
- None
Exploit likelihood
What each source reports
CVE List Score used
6.5
URL Redirection to Untrusted Site ('Open Redirect') in Products.isurlinportal
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.
- Record
CVE-2021-32806- CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N - Weakness
- CWE-601
- Updated
- 2026-11-02
EUVDEUVD-2021-0199
6.5
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.
- Record
EUVD-2021-0199- CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N - Updated
- 2026-11-03
GitHub AdvisoriesGHSA-q3m9-9fj2-mfwr
7.1
URL Redirection to Untrusted Site ('Open Redirect') in Products.isurlinportal
Impact
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.
But the url https:example.org without slashes tricks our code and it 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 you to their site, especially as part of a phishing attack.
Patches
The problem has been patched in Products.isurlinportal 1.2.0.
This is a recommended upgrade for all users of Plone 4.3 and 5, on Python 2.7 or higher.
It has not been tested on earlier Plone or Python versions.
Upcoming Plone 5.2.5 and higher will include the new version.
Discovered
This vulnerability was discovered and reported by Yuji Tounai of Mitsui Bussan Secure Directions, Inc. Thank you!
For more information
If you have any questions or comments about this advisory:
- Email the Plone Security Team at [email protected], especially when you think you have discovered a security problem or when you are not sure.
- Open an issue in the tracker if your question or comment can be public.
- Record
GHSA-q3m9-9fj2-mfwr- CVSS 4.0
- 7.1 High
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N - CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N - Weakness
- CWE-601
- Updated
- 2026-11-02
NVD
6.5
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.
- Record
CVE-2021-32806- CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N - CVSS 3.1
- 6.1 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N - CVSS 2.0
- 5.8 Medium
AV:N/AC:M/Au:N/C:P/I:P/A:N - Weakness
- CWE-601
- Updated
- 2026-11-02
OSV
6.1
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.
- Record
CVE-2021-32806- CVSS 3.1
- 6.1 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N - Updated
- 2026-11-02
OSVGHSA-q3m9-9fj2-mfwr
7.1
URL Redirection to Untrusted Site ('Open Redirect') in Products.isurlinportal
Impact
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.
But the url https:example.org without slashes tricks our code and it 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 you to their site, especially as part of a phishing attack.
Patches
The problem has been patched in Products.isurlinportal 1.2.0.
This is a recommended upgrade for all users of Plone 4.3 and 5, on Python 2.7 or higher.
It has not been tested on earlier Plone or Python versions.
Upcoming Plone 5.2.5 and higher will include the new version.
Discovered
This vulnerability was discovered and reported by Yuji Tounai of Mitsui Bussan Secure Directions, Inc. Thank you!
For more information
If you have any questions or comments about this advisory:
- Email the Plone Security Team at [email protected], especially when you think you have discovered a security problem or when you are not sure.
- Open an issue in the tracker if your question or comment can be public.
- Record
GHSA-q3m9-9fj2-mfwr- CVSS 4.0
- 7.1 High
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N - CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N - Weakness
- CWE-601
- Updated
- 2026-11-02
OSVPYSEC-2021-323 No score
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.
- Record
PYSEC-2021-323- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
products-isurlinportalPyPI |
before 1.2.0 | 1.2.0 |
products-isurlinportalPyPI |
before 1.2.0, plus listed versions 1.0.01.1.01.1.1 |
1.2.0 |
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2021-32806 is a medium vulnerability (CVSS 6.5) in Plone Isurlinportal, published August 2, 2021. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 1.03%, the 63rd percentile. Fixed in products-isurlinportal 1.2.0.
References
github.com/plone/Products.isurlinportal/security/advisories/GHSA-q3m9-9fj2-mfwr
github.com/plone/Products.isurlinportal/commit/d4fd34990d18adf05a10dc5e2bb4b066798280ba
jvn.jp/en/jp/JVN50804280/index.html
nvd.nist.gov/vuln/detail/CVE-2021-32806
github.com/pypa/advisory-database/tree/main/vulns/products-isurlinportal/PYSEC-2021-323.yaml
github.com/advisories/GHSA-q3m9-9fj2-mfwr
github.com/plone/Products.isurlinportal