CyberSecBulletin
CVE-2022-26889NVD status: Modified

Splunk Enterprise: Improper Limitation of a Pathname to a Restricted Directory

CVE-2022-26889 is a high-severity improper limitation of a pathname to a restricted directory vulnerability in Splunk Enterprise from Splunk, with a CVSS 3.1 base score of 8.8 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. Affected Splunk Enterprise versions: Version(s) before 8.1.2. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 1.5% chance of exploitation within 30 days, higher than 75% of scored CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update Splunk to 8.1.2 or a later version.
  2. Read the advisory on research.splunk.com for workarounds and exact fixed builds.
  3. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
  4. 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
SplunkSplunk EnterpriseVersion(s) before 8.1.2Not stated
SplunkSplunk8.1.0 up to, but not including, 8.1.28.1.2

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
UnchangedImpact stays within the vulnerable component.
Confidentiality
HighAll data handled by the component can be read.
Integrity
HighData or code can be modified at will.
Availability
HighThe component can be taken down completely.

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

Scoring systemScoreSeverityScored by
CVSS 3.18.8HighCNA (splunk.com)
CVSS 3.18.8HighNVD
CVSS 2.05.1MediumNVD

Official description

In Splunk Enterprise versions before 8.1.2, the uri path to load a relative resource within a web page is vulnerable to path traversal. It allows an attacker to potentially inject arbitrary content into the web page (e.g., HTML Injection, XSS) or bypass SPL safeguards for risky commands. The attack is browser-based. An attacker cannot exploit the attack at will and requires the attacker to initiate a request within the victim's browser (e.g., phishing).

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

The underlying weakness: Improper Limitation of a Pathname to a Restricted Directory

The product uses external input to construct a pathname that is intended to identify a file or directory that is located underneath a restricted parent directory, but the product does not properly neutralize special elements within the pathname that can cause the pathname to resolve to a location that is outside of the restricted directory.

How developers prevent this class of flaw

  • For any security checks that are performed on the client side, ensure that these checks are duplicated on the server side, in order to avoid CWE-602. Attackers can bypass the client-side checks by modifying values after the checks have been performed, or by changing the client to remove the client-side checks entirely. Then, these modified values would be submitted to the server.
  • Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid.
  • Use an application firewall that can detect attacks against this weakness. It can be beneficial in cases in which the code cannot be fixed (because it is controlled by a third party), as an emergency prevention measure while more comprehensive software assurance measures are applied, or to provide defense in depth.

More Improper Limitation of a Pathname to a Restricted Directory vulnerabilities (CWE-22)

Timeline

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

References

Other vulnerabilities in Splunk Enterprise

All Splunk Enterprise vulnerabilities

Recent Improper Limitation of a Pathname to a Restricted Directory vulnerabilities

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