CyberSecBulletin
CVE-2022-34321NVD status: Analyzed

Apache Pulsar: Missing Authentication for Critical Functionality

Published Updated By the CyberSecBulletin desk

CVE-2022-34321 is a high-severity missing authentication for critical functionality vulnerability in Apache Pulsar from Apache, with a CVSS 3.1 base score of 8.2 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 2.10.6, 2.11.3, 3.0.2 as the first without the flaw, so updating Apache Pulsar to one of those releases or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 1.76% chance of exploitation within 30 days, higher than 78% of scored CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update Apache Pulsar to 2.10.6 or 2.11.3 or 3.0.2 or 3.1.1, whichever matches your release line, or a later version.
  2. Update pulsar to 2.10.6 or 2.11.3 or 3.0.2 or 3.1.1, whichever matches your release line, or a later version.
  3. Read the advisory on lists.apache.org for workarounds and exact fixed builds.
  4. 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
ApacheApache Pulsar2.6.0 up to, but not including, 2.10.6; 2.11.0 up to, but not including, 2.11.3; 3.0.0 up to, but not including, 3.0.2; 3.1.0 up to, but not including, 3.1.12.10.6, 2.11.3, 3.0.2, 3.1.1
Apachepulsar2.6.0 up to, but not including, 2.10.6; 2.11.0 up to, but not including, 2.11.3; 3.0.0 up to, but not including, 3.0.2; 3.1.0 up to, but not including, 3.1.12.10.6, 2.11.3, 3.0.2, 3.1.1

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
LowLimited modification of data is possible.
Availability
NoneAvailability is not affected.

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

Scoring systemScoreSeverityScored by
CVSS 3.18.2HighCNA (apache.org)
CVSS 3.18.2HighNVD

Official description

Improper Authentication vulnerability in Apache Pulsar Proxy allows an attacker to connect to the /proxy-stats endpoint without authentication. The vulnerable endpoint exposes detailed statistics about live connections, along with the capability to modify the logging level of proxied connections without requiring proper authentication credentials. This issue affects Apache Pulsar versions from 2.6.0 to 2.10.5, from 2.11.0 to 2.11.2, from 3.0.0 to 3.0.1, and 3.1.0. The known risks include exposing sensitive information such as connected client IP and unauthorized logging level manipulation which could lead to a denial-of-service condition by significantly increasing the proxy's logging overhead. When deployed via the Apache Pulsar Helm chart within Kubernetes environments, the actual client IP might not be revealed through the load balancer's default behavior, which typically obscures the original source IP addresses when externalTrafficPolicy is being configured to "Cluster" by default. The /proxy-stats endpoint contains topic level statistics, however, in the default configuration, the topic level statistics aren't known to be exposed. 2.10 Pulsar Proxy users should upgrade to at least 2.10.6. 2.11 Pulsar Proxy users should upgrade to at least 2.11.3. 3.0 Pulsar Proxy users should upgrade to at least 3.0.2. 3.1 Pulsar Proxy users should upgrade to at least 3.1.1. Users operating versions prior to those listed above should upgrade to the aforementioned patched versions or newer versions. Additionally, it's imperative to recognize that the Apache Pulsar Proxy is not intended for direct exposure to the internet. The architectural design of Pulsar Proxy assumes that it will operate within a secured network environment, safeguarded by appropriate perimeter defenses.

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

The underlying weakness: Missing Authentication for Critical Functionality

The product does not perform any authentication for functionality that requires a provable user identity or consumes a significant amount of resources.

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. For example, consider using libraries with authentication capabilities such as OpenSSL or the ESAPI Authenticator.
  • When storing data in the cloud (e.g., S3 buckets, Azure blobs, Google Cloud Storage, etc.), use the provider's controls to require strong authentication for users who should be allowed to access the data.

More Missing Authentication for Critical Functionality vulnerabilities (CWE-306)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: yes, technical impact: partial).
  3. Record last changed materially (score, affected products, status or references).

References

Third-party and government advisories

Other vulnerabilities in Apache Pulsar

All Apache Pulsar vulnerabilities

Recent Missing Authentication for Critical Functionality vulnerabilities

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