What is CVE-2023-25194?A high-severity flaw in Kafka Connect, explained.
CVE-2023-25194 is a high-severity flaw (CVSS 8.8) in Kafka Connect from Apache, published on 7 February 2023. It is not on the list of flaws known to be exploited today. The latest forecast puts its chance of use in the next 30 days at 96%. If you run an affected version, plan in the vendor’s fix.
Published 7 February 2023. Record last updated 25 March 2025. We keep this page's data up to date.
What is CVE-2023-25194? In plain terms.
It can be attacked from anywhere on the internet with an ordinary user account, and nobody has to click anything. If it works, the attacker can read data, change data and take it offline.
A possible security vulnerability has been identified in Apache Kafka Connect API. This requires access to a Kafka Connect worker, and the ability to create/modify connectors on it with an arbitrary Kafka client SASL JAAS config and a SASL-based security protocol, which has been possible on Kafka Connect clusters since Apache Kafka Connect 2.3.0. When configuring the connector via the Kafka Connect REST API, an authenticated operator can set the `sasl.jaas.config` property for any of the connector's Kafka clients to "com.sun.security.auth.module.JndiLoginModule", which can be done via the `producer.override.sasl.jaas.config`, `consumer.override.sasl.jaas.config`, or `admin.override.sasl.jaas.config` properties. This will allow the server to connect to the attacker's LDAP server and deserialize the LDAP response, which the attacker can use to execute java deserialization gadget chains on the Kafka connect server. Attacker can cause unrestricted deserialization of untrusted data (or) RCE vulnerability when there are gadgets in the classpath.
Since Apache Kafka 3.0.0, users are allowed to specify these properties in connector configurations for Kafka Connect clusters running with out-of-the-box configurations. Before Apache Kafka 3.0.0, users may not specify these properties unless the Kafka Connect cluster has been reconfigured with a connector client override policy that permits them.
Since Apache Kafka 3.4.0, we have added a system property ("-Dorg.apache.kafka.disallowed.login.modules") to disable the problematic login modules usage in SASL JAAS configuration. Also by default "com.sun.security.auth.module.JndiLoginModule" is disabled in Apache Kafka Connect 3.4.0.
We advise the Kafka Connect users to validate connector configurations and only allow trusted JNDI configurations. Also examine connector dependencies for vulnerable versions and either upgrade their connectors, upgrading that specific dependency, or removing the connectors as options for remediation. Finally, in addition to leveraging the "org.apache.kafka.disallowed.login.modules" system property, Kafka Connect users can also implement their own connector client config override policy, which can be used to control which Kafka client properties can be overridden directly in a connector config and which cannot.
What kind of flaw is it?
- CWE-502Deserialization of Untrusted Data
How an attack on it works
Read straight from its severity rating, translated out of the shorthand.
- Where an attacker can beAnywhere on the internet
- How hard it is to pull offEasy: no special conditions
- Login needed firstAn ordinary user account
- Does someone have to clickNo, nobody has to do anything
- What an attacker getsCan read data, change data and take it offline
Severity vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Is CVE-2023-25194 being exploited? Not that we know of.
It is not on the list of flaws known to be exploited today. The latest forecast puts the chance of it being used in the next 30 days at 96%. That can change at any time, which is why we keep watching.
Timeline
- Published
- Record last updated
CVE-2023-25194 scores 76. Action: Patch now.
We keep the score of every published flaw up to date as the evidence changes. Four things go into the score, and evidence that criminals are actually using it counts most. In order:
- Evidence it is being exploitedBiggest factor
- How severe it isStrong factor
- How widely exposed it isSmaller factor
- Threat activity around itSmaller factor
85 and above is Critical. Anything confirmed as exploited is always marked for an emergency patch, whatever its score.
When CVE-2023-25194 matches software you track, it lands in your list with its score and the reasons behind it.
See your own ranked list →Who is affected by CVE-2023-25194? One product.
The published record lists 1 product from 1 vendor. If you run one of these, check your version, then go to the fix below.
- Application
Kafka Connect
by Apache
Affected versions2.3.0 to 3.3.2
How do I fix CVE-2023-25194? Four steps.
- Check whether you run itCompare your versions with the affected products above. Not sure what you run? Precursor Intelligence can work it out from your public website, or you can pick it from a list.
- Apply the vendor’s fixInstall the update named in the vendor’s advisory. We’ve put the advisories and patch notes first in the list.
- If you can’t patch todayFollow any mitigation the vendor publishes, and limit who can reach the affected system from the internet until the update is in.
- Keep an eye on itTrack the product and we tell you as soon as we spot this flaw on the list of exploited flaws, or a jump in its exploit likelihood.
Does CVE-2023-25194 affect you? We'll keep checking.
Looking flaws up one at a time doesn't scale. Tell us what you run once, and we tell you which flaws matter to you, in what order, and keep watching for new ones.
- Tell us what you runPick your software from a list, or let us work it out from your website.
- We match it to every flawOver 400,000 published flaws, checked against your list.
- Ranked by real-world riskA 0 to 100 score, led by evidence criminals are using it.
- Told as soon as we knowAn alert by email, in the app or by webhook to your own tools.
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1 new flaw affects software Acme tracks
A possible security vulnerability has been identified in Apache Kafka Connect API. This requires access to a Kafka Connect worker, and the ability to create/...
- Matched to
- Kafka Connect on Acme's software list
- What to do
- Plan in the vendor’s update
Sent to the alert recipients Acme chose. Also in the app and to Acme's webhook.
CVE-2023-25194 is a high-severity flaw in Kafka Connect from Apache, published on 7 February 2023. It can be attacked from anywhere on the internet with an ordinary user account, and nobody has to click anything. If it works, the attacker can read data, change data and take it offline.
It scores 8.8 out of 10 on the CVSS severity scale, which is high. Our risk score for CVE-2023-25194 is 76 out of 100, which is High. Its action is "Patch now". Not confirmed as exploited yet, but serious or likely enough that it should not wait for a quiet month.
It is not on the list of flaws known to be exploited today. The latest forecast puts the chance of it being used in the next 30 days at 96%. That can change at any time, which is why we keep watching.
For Kafka Connect from Apache: 2.3.0 to 3.3.2.
Install the update the vendor names in its advisory, linked first under "How do I fix" on this page. If you can't patch today, follow the vendor's mitigation and limit who can reach the affected system from the internet.