CyberSecBulletin
CVE-2023-40593NVD status: Modified

Splunk Enterprise: Uncontrolled Resource Consumption

CVE-2023-40593 is a high-severity uncontrolled resource consumption vulnerability in Splunk Enterprise 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 versions 8.2.12, 9.0.6 as the first without the flaw, so updating Splunk Enterprise to one of those releases or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.58% chance of exploitation within 30 days, which is low compared with other CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update Splunk Enterprise to 8.2.12 or 9.0.6, whichever matches your release line, or a later version.
  2. Update Splunk Cloud to 9.0.2205 or a later version.
  3. Update Splunk to 8.2.12 or 9.0.6, whichever matches your release line, or a later version.
  4. Read the advisory on advisory.splunk.com for workarounds and exact fixed builds.
  5. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.

Affected products and versions

VendorProductAffected versionsFixed in
SplunkSplunk Enterprise8.2 up to, but not including, 8.2.12; 9.0 up to, but not including, 9.0.68.2.12, 9.0.6
SplunkSplunk Cloudbefore 9.0.22059.0.2205
SplunkSplunk8.2.0 up to, but not including, 8.2.12; 9.0.0 up to, but not including, 9.0.68.2.12, 9.0.6
SplunkSplunk Cloud Platform9.0.2305.100 and earlierNot stated

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
NoneNo data is disclosed.
Integrity
NoneNothing can be modified.
Availability
HighThe component can be taken down completely.

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

Scoring systemScoreSeverityScored by
CVSS 3.16.3MediumCNA (splunk.com)
CVSS 3.17.5HighNVD

Official description

In Splunk Enterprise versions lower than 9.0.6 and 8.2.12, a malicious actor can send a malformed security assertion markup language (SAML) request to the `/saml/acs` REST endpoint which can cause a denial of service through a crash or hang of the Splunk daemon.

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

The underlying weakness: Uncontrolled Resource Consumption

The product does not properly control the allocation and maintenance of a limited resource.

How developers prevent this class of flaw

  • Ensure that protocols have specific limits of scale placed on them.
  • Ensure that all failures in resource allocation place the system into a safe posture.

More Uncontrolled Resource Consumption vulnerabilities (CWE-400)

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 Uncontrolled Resource Consumption vulnerabilities

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