CVE-2026-41855 is a high-severity (CVSS 8.1) Deserialization of Untrusted Data vulnerability in org.springframework:spring-jms. A fix is available for org.springframework:spring-jms — see the affected versions and patch details below.
Spring Framework Unsafe Deserialization via Jackson JMS Converters
Exploitation Status
No confirmed exploitation observed yet
- A successful exploit gives an attacker total control of the affected component, not partial access.
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2026-41855.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
Where this sits among everything scored
Real-World Exposure
org.springframework:spring-jms☕org.springframework:spring-jms☕org.springframework:spring-jms☕org.springframework:spring-jmsReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Maven packages — download data is not available via public APIs for these ecosystems.
Description
In an untrusted JMS environment, org.springframework.jms.support.converter.MappingJackson2MessageConverter and org.springframework.jms.support.converter.JacksonJsonMessageConverter allow arbitrary class instantiation, which can lead to unauthorized actions via gadget class deserialization.
Affected versions: Spring Framework 7.0.0 through 7.0.7; 6.2.0 through 6.2.18; 6.1.0 through 6.1.27; 5.3.0 through 5.3.48.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| ☕Maven | org.springframework:spring-jms | all versions | No fix |
| ☕Maven | org.springframework:spring-jms | ≥ 6.0.0 | No fix |
| ☕Maven | org.springframework:spring-jms | ≥ 6.2.0&&< 6.2.19 | 6.2.19org.springframework:spring-jms:6.2.19 |
| ☕Maven | org.springframework:spring-jms | ≥ 7.0.0-M1&&< 7.0.8 | 7.0.8org.springframework:spring-jms:7.0.8 |
Affected Products
spring frameworkvmwareDetection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for org.springframework:spring-jms, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
A fix is available for CVE-2026-41855; check the affected-versions list above or the advisory for the patched release of org.springframework:spring-jms, then make sure no transitive dependency still pins the vulnerable range.
Workarounds
Do not deserialise data from untrusted sources: where the format allows it, restrict deserialisation to an explicit allowlist of expected types, and prefer a data-only format (JSON, Protobuf) over one that can reconstruct arbitrary objects until you can upgrade.
Fixing This On Your OS
If you run this on a Linux distribution, patch through your package manager against the distro's own security advisory below — it tracks the exact backported fix for your release, which can ship on a different timeline (and sometimes a different severity) than the upstream project.
This Important flaw in Spring Framework, allowing arbitrary class instantiation via deserialization in an untrusted JMS environment, does not affect Red Hat products. The vulnerable code is not present in the execution path of Red Hat's supported configurations.
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability. Users of affected versions should upgrade to the corresponding fixed version.Source: Red Hat security advisory for CVE-2026-41855 (CC BY 4.0)
Frequently Asked Questions
Is CVE-2026-41855 in your dependencies?
Find it across Maven, including transitive dependencies.