CyberSecBulletin
CVE-2022-22691NVD status: Modified

Umbraco CMS: Inconsistent Interpretation of HTTP Requests

Published Updated By the CyberSecBulletin desk

CVE-2022-22691 is a high-severity inconsistent interpretation of HTTP requests vulnerability in Umbraco CMS from Umbraco, with a CVSS 3.1 base score of 7.4 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, but only if a user takes part, for example by opening a link or file. The record lists version 9.2.0 as the first without the flaw, so updating Umbraco CMS to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 1.05% chance of exploitation within 30 days, higher than 65% of scored CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update Umbraco CMS to 9.2.0 or a later version.
  2. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
  3. Because the attack needs a user to take part, warn users about unexpected links and files related to this product until it is patched.

Affected products and versions

VendorProductAffected versionsFixed in
UmbracoUmbraco CMSbefore 9.2.09.2.0

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
NoneNo account or login is needed.
User interaction
RequiredA user must take an action such as opening a file or link.
Scope
ChangedThe attack can reach beyond the vulnerable component into other systems.
Confidentiality
HighAll data handled by the component can be read.
Integrity
NoneNothing can be modified.
Availability
NoneAvailability is not affected.

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:N/A:N. Scored by NVD.

Scoring systemScoreSeverityScored by
CVSS 3.16.8MediumCNA (appcheck-ng.com)
CVSS 3.17.4HighNVD
CVSS 2.04.3MediumNVD

Official description

The password reset component deployed within Umbraco uses the hostname supplied within the request host header when building a password reset URL. It may be possible to manipulate the URL sent to Umbraco users when so that it points to the attackers server thereby disclosing the password reset token if/when the link is followed. A related vulnerability (CVE-2022-22690) could allow this flaw to become persistent so that all password reset URLs are affected persistently following a successful attack. See the AppCheck advisory for further information and associated caveats.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Inconsistent Interpretation of HTTP Requests

The product acts as an intermediary HTTP agent (such as a proxy or firewall) in the data flow between two entities such as a client and server, but it does not interpret malformed HTTP requests or responses in ways that are consistent with how the messages will be processed by those entities that are at the ultimate destination.

How developers prevent this class of flaw

  • Use a web server that employs a strict HTTP parsing procedure, such as Apache.
  • Terminate the client session after each request.

More Inconsistent Interpretation of HTTP Requests vulnerabilities (CWE-444)

Timeline

  1. CVE record published.
  2. Record last changed materially (score, affected products, status or references).

References

Other vulnerabilities in Umbraco CMS

All Umbraco CMS vulnerabilities

Recent Inconsistent Interpretation of HTTP Requests vulnerabilities

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