Remote code execution via unchecked ExternalizableLite instantiation
Published Apr 22, 2021 · Updated Sep 26, 2024
Deserialization in Oracle WebLogic Server 12.2.1.3.0, 12.2.1.4.0, and 14.1.1.0.0 allows remote attackers to execute code via T3 or IIOP. The Coherence Container's ExternalizableLite input path reads an attacker-controlled class name, instantiates that class, invokes readExternal, and later calls readResolve without the expected deserialization blocklist. Unauthenticated network access to a T3 or IIOP listener is sufficient, and successful exploitation grants control of the WebLogic Server process.
Summary
What happened
Deserialization in Oracle WebLogic Server 12.2.1.3.0, 12.2.1.4.0, and 14.1.1.0.0 allows remote attackers to execute code via T3 or IIOP. The Coherence Container's ExternalizableLite input path reads an attacker-controlled class name, instantiates that class, invokes readExternal, and later calls readResolve without the expected deserialization blocklist. Unauthenticated network access to a T3 or IIOP listener is sufficient, and successful exploitation grants control of the WebLogic Server process.
The record
- CVE
- CVE-2021-2135
- Published
- Apr 22, 2021
- Updated
- Sep 26, 2024
- Vendor
- Oracle Corporation
- Product
- Oracle WebLogic Server
- Classifications
- T1190
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Apr 22, 2021CVE publishedPublication date reported by the CVE source.
- Sep 26, 2024Record 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=12.2.1.3.0
- Affected versionversion=12.2.1.4.0
- Affected versionversion=14.1.1.0.0
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
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Weakness, pattern, technique
Public exploit references
- ProjectDiscovery nuclei CVE-2021-2135 templatefunctional · demonstrated
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Technologies
Your stack
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Your stack
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