CVE-2024-27894

CVE-2024-27894 is a high-severity vulnerability in Apache Pulsar with a CVSS 3.x base score of 8.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-20.

Key facts

Description

The Pulsar Functions Worker includes a capability that permits authenticated users to create functions where the function's implementation is referenced by a URL. The supported URL schemes include "file", "http", and "https". When a function is created using this method, the Functions Worker will retrieve the implementation from the URL provided by the user. However, this feature introduces a vulnerability that can be exploited by an attacker to gain unauthorized access to any file that the Pulsar Functions Worker process has permissions to read. This includes reading the process environment which potentially includes sensitive information, such as secrets. Furthermore, an attacker could leverage this vulnerability to use the Pulsar Functions Worker as a proxy to access the content of remote HTTP and HTTPS endpoint URLs. This could also be used to carry out denial of service attacks. This vulnerability also applies to the Pulsar Broker when it is configured with "functionsWorkerEnabled=true". This issue affects Apache Pulsar versions from 2.4.0 to 2.10.5, from 2.11.0 to 2.11.3, from 3.0.0 to 3.0.2, from 3.1.0 to 3.1.2, and 3.2.0. 2.10 Pulsar Function Worker users should upgrade to at least 2.10.6. 2.11 Pulsar Function Worker users should upgrade to at least 2.11.4. 3.0 Pulsar Function Worker users should upgrade to at least 3.0.3. 3.1 Pulsar Function Worker users should upgrade to at least 3.1.3. 3.2 Pulsar Function Worker users should upgrade to at least 3.2.1. Users operating versions prior to those listed above should upgrade to the aforementioned patched versions or newer versions. The updated versions of Pulsar Functions Worker will, by default, impose restrictions on the creation of functions using URLs. For users who rely on this functionality, the Function Worker configuration provides two configuration keys: "additionalEnabledConnectorUrlPatterns" and "additionalEnabledFunctionsUrlPatterns". These keys allow users to specify a set of URL patterns that are permitted, enabling the creation of functions using URLs that match the defined patterns. This approach ensures that the feature remains available to those who require it, while limiting the potential for unauthorized access and exploitation.

Frequently asked questions

What is CVE-2024-27894?
The Pulsar Functions Worker includes a capability that permits authenticated users to create functions where the function's implementation is referenced by a URL. The supported URL schemes include "file", "http", and "https". When a function is created using this method, the Functions Worker will retrieve the implementation from the URL provided by the user. However, this feature introduces a vulnerability that can be exploited by an attacker to gain unauthorized access to any file that the Pulsar Functions Worker process has permissions to read. This includes reading the process environment which potentially includes sensitive information, such as secrets. Furthermore, an attacker could leverage this vulnerability to use the Pulsar Functions Worker as a proxy to access the content of remote HTTP and HTTPS endpoint URLs. This could also be used to carry out denial of service attacks. This vulnerability also applies to the Pulsar Broker when it is configured with "functionsWorkerEnabled=true". This issue affects Apache Pulsar versions from 2.4.0 to 2.10.5, from 2.11.0 to 2.11.3, from 3.0.0 to 3.0.2, from 3.1.0 to 3.1.2, and 3.2.0. 2.10 Pulsar Function Worker users should upgrade to at least 2.10.6. 2.11 Pulsar Function Worker users should upgrade to at least 2.11.4. 3.0 Pulsar Function Worker users should upgrade to at least 3.0.3. 3.1 Pulsar Function Worker users should upgrade to at least 3.1.3. 3.2 Pulsar Function Worker users should upgrade to at least 3.2.1. Users operating versions prior to those listed above should upgrade to the aforementioned patched versions or newer versions. The updated versions of Pulsar Functions Worker will, by default, impose restrictions on the creation of functions using URLs. For users who rely on this functionality, the Function Worker configuration provides two configuration keys: "additionalEnabledConnectorUrlPatterns" and "additionalEnabledFunctionsUrlPatterns". These keys allow users to specify a set of URL patterns that are permitted, enabling the creation of functions using URLs that match the defined patterns. This approach ensures that the feature remains available to those who require it, while limiting the potential for unauthorized access and exploitation.
How severe is CVE-2024-27894?
CVE-2024-27894 has a CVSS 3.x base score of 8.5, rated high severity. It is exploitable over network with high attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2024-27894 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (77th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2024-27894?
CVE-2024-27894 primarily affects Apache Pulsar. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2024-27894?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
Does CVE-2024-27894 have an EU (EUVD) identifier?
Yes. CVE-2024-27894 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2024-0894.
When was CVE-2024-27894 published?
CVE-2024-27894 was published on 2024-03-12 and last updated on 2026-06-17.

References

Affected products (2)

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