Security Bulletin: Multiple Vulnerabilities in IBM Operator for Apache Flink

Vulnerability Details

CVEID:   CVE-2021-39194
DESCRIPTION:   kaml is an open source implementation of the YAML format with support for kotlinx.serialization. In affected versions attackers that could provide arbitrary YAML input to an application that uses kaml could cause the application to endlessly loop while parsing the input. This could result in resource starvation and denial of service. This only affects applications that use polymorphic serialization with the default tagged polymorphism style. Applications using the property polymorphism style are not affected. YAML input for a polymorphic type that provided a tag but no value for the object would trigger the issue. Version 0.35.3 or later contain the fix for this issue.
CWE:   CWE-835: Loop with Unreachable Exit Condition ('Infinite Loop')
CVSS Source:   IBM X-Force
CVSS Base score:   4.3
CVSS Vector:   (CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L)

CVEID:   CVE-2025-24970
DESCRIPTION:   Netty, an asynchronous, event-driven network application framework, has a vulnerability starting in version 4.1.91.Final and prior to version 4.1.118.Final. When a special crafted packet is received via SslHandler it doesn't correctly handle validation of such a packet in all cases which can lead to a native crash. Version 4.1.118.Final contains a patch. As workaround its possible to either disable the usage of the native SSLEngine or change the code manually.
CWE:   CWE-20: Improper Input Validation
CVSS Source:   security-advisories@github.com
CVSS Base score:   7.5
CVSS Vector:   (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H)

CVEID:   CVE-2025-27818
DESCRIPTION:   A possible security vulnerability has been identified in Apache Kafka. This requires access to a alterConfig to the cluster resource, or 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 clusters since Apache Kafka 2.0.0 (Kafka Connect 2.3.0). When configuring the broker via config file or AlterConfig command, or connector via the Kafka 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.LdapLoginModule", 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 3.9.1/4.0.0, 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,com.sun.security.auth.module.LdapLoginModule" are disabled in Apache Kafka Connect 3.9.1/4.0.0. We advise the Kafka users to validate connector configurations and only allow trusted LDAP 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.
CWE:   CWE-502: Deserialization of Untrusted Data
CVSS Source:   CISA ADP
CVSS Base score:   8.8
CVSS Vector:   (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H)

CVEID:   CVE-2025-27819
DESCRIPTION:   In CVE-2023-25194, we announced the RCE/Denial of service attack via SASL JAAS JndiLoginModule configuration in Kafka Connect API. But not only Kafka Connect API is vulnerable to this attack, the Apache Kafka brokers also have this vulnerability. To exploit this vulnerability, the attacker needs to be able to connect to the Kafka cluster and have the AlterConfigs permission on the cluster resource. 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 3.4.0, and "com.sun.security.auth.module.JndiLoginModule,com.sun.security.auth.module.LdapLoginModule" is disabled by default in in Apache Kafka 3.9.1/4.0.0
CWE:   CWE-502: Deserialization of Untrusted Data
CVSS Source:   CISA ADP
CVSS Base score:   7.5
CVSS Vector:   (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H)

CVEID:   CVE-2024-31141
DESCRIPTION:   Files or Directories Accessible to External Parties, Improper Privilege Management vulnerability in Apache Kafka Clients. Apache Kafka Clients accept configuration data for customizing behavior, and includes ConfigProvider plugins in order to manipulate these configurations. Apache Kafka also provides FileConfigProvider, DirectoryConfigProvider, and EnvVarConfigProvider implementations which include the ability to read from disk or environment variables. In applications where Apache Kafka Clients configurations can be specified by an untrusted party, attackers may use these ConfigProviders to read arbitrary contents of the disk and environment variables. In particular, this flaw may be used in Apache Kafka Connect to escalate from REST API access to filesystem/environment access, which may be undesirable in certain environments, including SaaS products. This issue affects Apache Kafka Clients: from 2.3.0 through 3.5.2, 3.6.2, 3.7.0. Users with affected applications are recommended to upgrade kafka-clients to version >=3.8.0, and set the JVM system property "org.apache.kafka.automatic.config.providers=none". Users of Kafka Connect with one of the listed ConfigProvider implementations specified in their worker config are also recommended to add appropriate "allowlist.pattern" and "allowed.paths" to restrict their operation to appropriate bounds. For users of Kafka Clients or Kafka Connect in environments that trust users with disk and environment variable access, it is not recommended to set the system property. For users of the Kafka Broker, Kafka MirrorMaker 2.0, Kafka Streams, and Kafka command-line tools, it is not recommended to set the system property.
CWE:   CWE-269: Improper Privilege Management
CVSS Source:   IBM X-Force
CVSS Base score:   6.8
CVSS Vector:   (CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N)

CVEID:   CVE-2023-25194
DESCRIPTION:   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.
CWE:   CWE-502: Deserialization of Untrusted Data
CVSS Source:   IBM X-Force
CVSS Base score:   8.8
CVSS Vector:   (CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H)

CVEID:   CVE-2021-38153
DESCRIPTION:   Some components in Apache Kafka use `Arrays.equals` to validate a password or key, which is vulnerable to timing attacks that make brute force attacks for such credentials more likely to be successful. Users should upgrade to 2.8.1 or higher, or 3.0.0 or higher where this vulnerability has been fixed. The affected versions include Apache Kafka 2.0.0, 2.0.1, 2.1.0, 2.1.1, 2.2.0, 2.2.1, 2.2.2, 2.3.0, 2.3.1, 2.4.0, 2.4.1, 2.5.0, 2.5.1, 2.6.0, 2.6.1, 2.6.2, 2.7.0, 2.7.1, and 2.8.0.
CWE:   CWE-203: Observable Discrepancy
CVSS Source:   IBM X-Force
CVSS Base score:   7.5
CVSS Vector:   (CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N)

CVEID:   CVE-2025-25193
DESCRIPTION:   Netty, an asynchronous, event-driven network application framework, has a vulnerability in versions up to and including 4.1.118.Final. An unsafe reading of environment file could potentially cause a denial of service in Netty. When loaded on an Windows application, Netty attempts to load a file that does not exist. If an attacker creates such a large file, the Netty application crash. A similar issue was previously reported as CVE-2024-47535. This issue was fixed, but the fix was incomplete in that null-bytes were not counted against the input limit. Commit d1fbda62d3a47835d3fb35db8bd42ecc205a5386 contains an updated fix.
CWE:   CWE-400: Uncontrolled Resource Consumption
CVSS Source:   NVD
CVSS Base score:   5.5
CVSS Vector:   (CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H)

CVEID:   CVE-2024-47535
DESCRIPTION:   Netty is an asynchronous event-driven network application framework for rapid development of maintainable high performance protocol servers & clients. An unsafe reading of environment file could potentially cause a denial of service in Netty. When loaded on an Windows application, Netty attempts to load a file that does not exist. If an attacker creates such a large file, the Netty application crashes. This vulnerability is fixed in 4.1.115.
CWE:   CWE-400: Uncontrolled Resource Consumption
CVSS Source:   CVE.org
CVSS Base score:   5.5
CVSS Vector:   (CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H)

CVEID:   CVE-2025-58057
DESCRIPTION:   Netty is an asynchronous event-driven network application framework for rapid development of maintainable high performance protocol servers & clients. In netty-codec-compression versions 4.1.124.Final and below, and netty-codec versions 4.2.4.Final and below, when supplied with specially crafted input, BrotliDecoder and certain other decompression decoders will allocate a large number of reachable byte buffers, which can lead to denial of service. BrotliDecoder.decompress has no limit in how often it calls pull, decompressing data 64K bytes at a time. The buffers are saved in the output list, and remain reachable until OOM is hit. This is fixed in versions 4.1.125.Final of netty-codec and 4.2.5.Final of netty-codec-compression.
CWE:   CWE-409: Improper Handling of Highly Compressed Data (Data Amplification)
CVSS Source:   NVD
CVSS Base score:   7.5
CVSS Vector:   (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H)

CVEID:   CVE-2025-55163
DESCRIPTION:   Netty is an asynchronous, event-driven network application framework. Prior to versions 4.1.124.Final and 4.2.4.Final, Netty is vulnerable to MadeYouReset DDoS. This is a logical vulnerability in the HTTP/2 protocol, that uses malformed HTTP/2 control frames in order to break the max concurrent streams limit - which results in resource exhaustion and distributed denial of service. This issue has been patched in versions 4.1.124.Final and 4.2.4.Final.
CWE:   CWE-770: Allocation of Resources Without Limits or Throttling
CVSS Source:   NVD
CVSS Base score:   7.5
CVSS Vector:   (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H)

CVEID:   CVE-2024-58103
DESCRIPTION:   Square Wire before 5.2.0 does not enforce a recursion limit on nested groups in ByteArrayProtoReader32.kt and ProtoReader.kt.
CWE:   CWE-674: Uncontrolled Recursion
CVSS Source:   cve@mitre.org
CVSS Base score:   5.8
CVSS Vector:   (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:L)

CVEID:   CVE-2024-38808
DESCRIPTION:   In Spring Framework versions 5.3.0 - 5.3.38 and older unsupported versions, it is possible for a user to provide a specially crafted Spring Expression Language (SpEL) expression that may cause a denial of service (DoS) condition. Specifically, an application is vulnerable when the following is true: * The application evaluates user-supplied SpEL expressions.
CWE:   CWE-770: Allocation of Resources Without Limits or Throttling
CVSS Source:   VMware
CVSS Base score:   4.3
CVSS Vector:   (CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L)