CVE-2026-41731 is a high-severity insecure deserialization vulnerability in org.springframework.kafka:spring-kafka (maven), affecting versions >= 4.0.0, <= 4.0.5. It is fixed in 4.0.6, 3.3.16.
JsonKafkaHeaderMapper and the deprecated DefaultKafkaHeaderMapper matched type headers against trusted packages using a prefix check, meaning that trusting any package implicitly trusted all of its subpackages. Combined with Jackson's default bean deserialization, a producer could supply crafted header values that caused the consumer to deserialize arbitrary JDK types. Affected versions: Spring for Apache Kafka 4.0.0 through 4.0.5; 3.3.0 through 3.3.15; 3.2.0 through 3.2.13; 2.9.0 through 2.9.13; 2.8.0 through 2.8.11.
Untrusted serialized data is processed by a deserializer that can instantiate arbitrary objects or execute code as a side effect. Typical impact: arbitrary code execution or logic abuse.
CVE-2026-41731 has a CVSS score of 8.1 (High). The vector is network-reachable, no privileges required, and no user interaction. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment.
A fixed version is available (4.0.6, 3.3.16). Upgrading removes the vulnerable code path.
maven
org.springframework.kafka:spring-kafka (>= 4.0.0, <= 4.0.5)org.springframework.kafka:spring-kafka (>= 3.3.0, <= 3.3.15)org.springframework.kafka:spring-kafka (>= 3.2.0, <= 3.2.13)org.springframework.kafka:spring-kafka (>= 2.9.0, <= 2.9.13)org.springframework.kafka:spring-kafka (<= 2.8.11)org.springframework.kafka:spring-kafka → 4.0.6 (maven)org.springframework.kafka:spring-kafka → 3.3.16 (maven)Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.
Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter instead of chasing every advisory.
Kodem's Application Detection and Response identifies whether CVE-2026-41731 is reachable in your applications. Explore runtime application protection for your team.
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Upgrade the following packages to resolve this vulnerability:
org.springframework.kafka:spring-kafka to 4.0.6 or laterorg.springframework.kafka:spring-kafka to 3.3.16 or laterKodem Kai can prioritize this vulnerability in your dependency tree and generate a fix recommendation.
CVE-2026-41731 is a high-severity insecure deserialization vulnerability in org.springframework.kafka:spring-kafka (maven), affecting versions >= 4.0.0, <= 4.0.5. It is fixed in 4.0.6, 3.3.16. Untrusted serialized data is processed by a deserializer that can instantiate arbitrary objects or execute code as a side effect.
CVE-2026-41731 has a CVSS score of 8.1 (High). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
org.springframework.kafka:spring-kafka (maven) versions >= 4.0.0, <= 4.0.5 is affected.
Yes. CVE-2026-41731 is fixed in 4.0.6, 3.3.16. Upgrade to this version or later.
Whether CVE-2026-41731 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
org.springframework.kafka:spring-kafka to 4.0.6 or laterorg.springframework.kafka:spring-kafka to 3.3.16 or later