CyberSecBulletin
CVE-2024-34361NVD status: Analyzed

pi-hole: Server-Side Request Forgery

CVE-2024-34361 is a high-severity server-side request forgery vulnerability in pi-hole, with a CVSS 3.1 base score of 8.8 out of 10. It can be exploited remotely over the network by an attacker with a low-privileged account, without any action from a user. The record lists version 5.18.3 as the first without the flaw, so updating pi-hole to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 2.83% chance of exploitation within 30 days, higher than 87% of scored CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update pi-hole to 5.18.3 or a later version.
  2. Read the advisory on github.com for workarounds and exact fixed builds.

Affected products and versions

VendorProductAffected versionsFixed in
Pi-holepi-hole< 5.18.3; before 5.18.35.18.3

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
LowA basic user account is enough.
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
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:L/UI:N/S:U/C:H/I:H/A:H. Scored by NVD.

Scoring systemScoreSeverityScored by
CVSS 3.18.5HighCNA (github.com)
CVSS 3.18.8HighNVD

Official description

Pi-hole is a DNS sinkhole that protects devices from unwanted content without installing any client-side software. A vulnerability in versions prior to 5.18.3 allows an authenticated user to make internal requests to the server via the `gravity_DownloadBlocklistFromUrl()` function. Depending on some circumstances, the vulnerability could lead to remote command execution. Version 5.18.3 contains a patch for this issue.

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

The underlying weakness: Server-Side Request Forgery

The web server receives a URL or similar request from an upstream component and retrieves the contents of this URL, but it does not sufficiently ensure that the request is being sent to the expected destination.

How developers prevent this class of flaw

  • If there is a known list of applications, IP, hostname, and/or domains to which the product is allowed to communicate, then use allowlists to ensure that outgoing requests are restricted to these known entities. The allowlists could be in the application code or possibly enforced by firewalls or network segmentation.
  • If the product is expected to be able to connect to arbitrary IP addresses or domains, consider using a denylist that includes private network addresses, internal domain names, etc. The denylist could be in the application code or possibly enforced by firewalls or network segmentation.

More Server-Side Request Forgery vulnerabilities (CWE-918)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: poc, automatable: no, technical impact: total).
  3. Record last changed materially (score, affected products, status or references).

References

Other vulnerabilities in pi-hole

All pi-hole vulnerabilities

Recent Server-Side Request Forgery vulnerabilities

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