Cross-site Scripting and Open Redirect in Products.ATContentTypes

Description

Impact

Plone is vulnerable to reflected cross site scripting and open redirect when an attacker can get a compromised version of the image_view_fullscreen page in a cache, for example in Varnish.
The technique is known as cache poisoning.
Any later visitor can get redirected when clicking on a link on this page.
Usually only anonymous users are affected, but this depends on your cache settings.

Patches

A new version 3.0.6 of Products.ATContentTypes has been released with a fix.
This version works on Plone 5.2 (Python 2 only) and will be included in Plone 5.2.7.

Note that the Products.CMFPlone package has the same problem in the 4.3 series.
plone.app.contenttypes has the same problem in all versions, see advisory.
For all unpatched versions of the three packages, you can use the following workaround.

Workaround

Make sure the image_view_fullscreen page is not stored in the cache.
In Plone:

  • Login as Manager and go to Site Setup.
  • Go to the 'Caching' control panel. If this does not exist, or 'Enable caching' is not checked, you should normally not be vulnerable.
  • Click on the tab 'Caching operations'.
  • Under 'Legacy template mappings' locate the ruleset 'Content item view'.
  • From the last column ('Templates') remove 'image_view_fullscreen'.
  • Click on Save.

Reporter

This vulnerability was responsibly disclosed to the Plone Security Team by Gustav Hansen, F-Secure Consulting. Thank you!

For more information

If you have any questions or comments about this advisory, email us at [email protected]
This is also the correct address to use when you want to report a possible vulnerability.
See our security report policy.

Basic information

Type
reviewed
Severity
medium
Advisory on GitHub
Open advisory ↗
Repository advisory
Open repository advisory ↗
Source code
Browse source ↗
Published (advisory)
2022-01-28 23:10:37 UTC
Updated
2024-10-21 20:59:15 UTC
GitHub reviewed
2022-01-28 22:15:57 UTC
NVD published
2022-01-28

EPSS Score

Score Percentile
0.32% 54.51%

CVSS Scores

Base score Version Severity Vector
4.3 3.1
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:N)
Service keeps running; no real outage angle.
5.3 4.0
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network.
Attack complexity (AC:L)
Exploitation conditions are straightforward and stable.
Attack requirements (AT:N)
No additional preconditions are required beyond normal reachability.
Privileges required (PR:N)
No privileges are required.
User interaction (UI:P)
A user has to participate (for example click/open/approve).
Vulnerable system confidentiality impact (VC:L)
Limited confidentiality impact on the vulnerable system.
Vulnerable system integrity impact (VI:N)
No integrity impact on the vulnerable system.
Vulnerable system availability impact (VA:N)
No availability impact on the vulnerable system.
Subsequent system confidentiality impact (SC:N)
No confidentiality impact on subsequent systems.
Subsequent system integrity impact (SI:N)
No integrity impact on subsequent systems.
Subsequent system availability impact (SA:N)
No availability impact on subsequent systems.

Identifiers

CWEs

CWE id Name
CWE-79 Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
CWE-601 URL Redirection to Untrusted Site ('Open Redirect')

Affected packages (1)

Vulnerable version ranges and first patched releases as published by GitHub.

Ecosystem Package Vulnerable range First patched Vulnerable functions
pip Products.ATContentTypes < 3.0.6 3.0.6

References

cvelogic Threat Intelligence