Universal Forwarder: Incorrect Permission Assignment for Critical Resource
CVE-2022-32155 is a high-severity incorrect permission assignment for critical resource vulnerability in Universal Forwarder from Splunk, with a CVSS 3.1 base score of 7.5 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. The record lists version 9.0 as the first without the flaw, so updating Universal Forwarder to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 2.01% chance of exploitation within 30 days, higher than 81% of scored CVEs.
High severity with no evidence of exploitation so far.
What to do
- Update Universal Forwarder to 9.0 or a later version.
- Update Splunk to 9.0 or a later version.
- Update Splunk Cloud Platform to 8.2.2106 or a later version.
- Read the advisory on docs.splunk.com for workarounds and exact fixed builds.
- Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Splunk | Universal Forwarder | 9.0 up to, but not including, 9.0 | 9.0 |
| Splunk | Splunk | before 9.0 | 9.0 |
| Splunk | Splunk Cloud Platform | before 8.2.2106 | 8.2.2106 |
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
- NoneNo action by a victim is required.
- Scope
- UnchangedImpact stays within the vulnerable component.
- 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:N/S:U/C:H/I:N/A:N. Scored by NVD.
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 3.1 | 7.5 | High | NVD |
| CVSS 2.0 | 5.0 | Medium | NVD |
Official description
In universal forwarder versions before 9.0, management services are available remotely by default. When not required, it introduces a potential exposure, but it is not a vulnerability. If exposed, we recommend each customer assess the potential severity specific to your environment. In 9.0, the universal forwarder now binds the management port to localhost preventing remote logins by default. If management services are not required in versions before 9.0, set disableDefaultPort = true in server.conf OR allowRemoteLogin = never in server.conf OR mgmtHostPort = localhost in web.conf. See Configure universal forwarder management security (https://docs.splunk.com/Documentation/Splunk/9.0.0/Security/EnableTLSCertHostnameValidation#Configure_universal_forwarder_management_security) for more information on disabling the remote management services.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Incorrect Permission Assignment for Critical Resource
The product specifies permissions for a security-critical resource in a way that allows that resource to be read or modified by unintended actors.
How developers prevent this class of flaw
- When using a critical resource such as a configuration file, check to see if the resource has insecure permissions (such as being modifiable by any regular user), and generate an error or even exit the software if there is a possibility that the resource could have been modified by an unauthorized party.
- Divide the software into anonymous, normal, privileged, and administrative areas. Reduce the attack surface by carefully defining distinct user groups, privileges, and/or roles. Map these against data, functionality, and the related resources. Then set the permissions accordingly. This will allow you to maintain more fine-grained control over your resources.
- During program startup, explicitly set the default permissions or umask to the most restrictive setting possible. Also set the appropriate permissions during program installation. This will prevent you from inheriting insecure permissions from any user who installs or runs the program.
More Incorrect Permission Assignment for Critical Resource vulnerabilities (CWE-732)
Timeline
- CVE record published.
- Record last changed materially (score, affected products, status or references).
References
Advisories
Other vulnerabilities in Universal Forwarder
- 8.0 High severity
- 8.8 High severity
- 8.8 High severity
- 9.1 Critical severity
- 7.5 High severity
- 9.8 Critical severity
Recent Incorrect Permission Assignment for Critical Resource vulnerabilities
- 7.8 High severity
- 9.8 Critical severity
- 7.5 High severity
- 7.5 High severity
- 7.8 High severity
- 7.5 High severity
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