Class-registration bypass during Java lambda deserialization
Published Jul 21, 2026 · Updated Jul 21, 2026
Deserialization in Apache Fory before 1.4.0 allows remote attackers to bypass class-registration checks through crafted Java lambda data. Apache has disclosed that the bypass affects only the lambda capture class, but has not published the responsible function or exact wrong operation. Exposure requires an application to deserialize attacker-controlled Fory data with class registration enabled; broader lambda classes are not reported as affected.
Summary
What happened
Deserialization in Apache Fory before 1.4.0 allows remote attackers to bypass class-registration checks through crafted Java lambda data. Apache has disclosed that the bypass affects only the lambda capture class, but has not published the responsible function or exact wrong operation. Exposure requires an application to deserialize attacker-controlled Fory data with class registration enabled; broader lambda classes are not reported as affected.
The record
- CVE
- CVE-2026-64606
- Published
- Jul 21, 2026
- Updated
- Jul 21, 2026
- Vendor
- The Apache Software Foundation
- Product
- Apache Fory
- Classifications
- CWE-502
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Jul 21, 2026CVE publishedPublication date reported by the CVE source.
- Jul 21, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=0.11.0 <1.4.0
- Affected versionversion=0.5.0 <0.11.0
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
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Weakness, pattern, technique
Public exploit references
No public exploit references are available in this record.
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Technologies
Your stack
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Your stack
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