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CriticalCISA KEVExploited in the wildPublic exploit

Oracle Coherence / WebLogic T3 Deserialization RCE (CVE-2020-2555)

IdentifiersCVE-2020-2555CWE-502· Deserialization of Untrusted Data

CVE-2020-2555 is an unauthenticated Java deserialization vulnerability in Oracle Coherence, affecting Oracle Fusion Middleware deployments including Oracle WebLogic environments that expose the T3 protocol and include vulnerable Coherence components. A remote attacker can send a crafted serialized Java object, including a javax.management.BadAttributeValueExpException wrapper and a gadget chain using Coherence classes such as com.tangosol.util.filter.LimitFilter, com.tangosol.util.extractor.ChainedExtractor, and com.tangosol.util.extractor.ReflectionExtractor, to trigger unsafe deserialization and invoke java.lang.Runtime methods. Oracle lists affected versions as 3.7.1.0, 12.1.3.0.0, 12.2.1.3.0, and 12.2.1.4.0. The issue is network exploitable over T3 without authentication and can lead to full compromise of the Oracle Coherence service.

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ANALYST BRIEF

Impact, mitigation & remediation

What it means. What to do now. Patch path, mitigations, and the assume-compromise checklist.

Impact

What an attacker gets, and what they’ve been doing with it.

Successful exploitation can result in complete takeover of the affected Oracle Coherence/WebLogic instance, with high impact to confidentiality, integrity, and availability. In practical terms, this provides unauthenticated remote code execution in the context of the vulnerable service, enabling arbitrary command execution, deployment of follow-on payloads, data theft, service manipulation, persistence, and potential lateral movement from the compromised middleware host.

Mitigation

If you can’t patch tonight, do this now.

If immediate patching is not possible, restrict or block network access to the T3/T3S service from untrusted networks, remove internet exposure, and enforce segmentation so only trusted application tiers can reach the service. Disable unused protocols/components where feasible, monitor logs and network telemetry for suspicious T3 deserialization activity and exploitation attempts, and review Oracle guidance for temporary workarounds. Because exploitation is unauthenticated and low complexity, exposure reduction should be treated as urgent.

Remediation

Patch, then assume compromise.

Apply Oracle's security updates for CVE-2020-2555, including the fixes delivered in Oracle's Critical Patch Update guidance for affected Fusion Middleware/Coherence products. Upgrade affected versions 3.7.1.0, 12.1.3.0.0, 12.2.1.3.0, and 12.2.1.4.0 to vendor-fixed releases or the latest supported patched versions. Validate that all WebLogic/Coherence deployments, including embedded or bundled instances in downstream Oracle products, have received the relevant CPU patches.
PUBLIC EXPLOITS

Exploits

6 valid exploits after Mallory filtered fakes, detection scripts, and README-only repos (1 hidden).

VALID 6 / 7 TOTALView more in app
exphubMaturityPoCVerified exploit

This repository is a comprehensive exploit library (exphub) containing operational exploit scripts for a wide range of high-profile vulnerabilities affecting popular enterprise software. The structure is organized by product (e.g., drupal/, f5/, fastjson/, jboss/, nexus/, ofbiz/, shiro/, solr/, spring/, struts2/, tomcat/, weblogic/), with each directory containing Python or Java scripts for specific CVEs. The scripts are primarily remote code execution (RCE) exploits, but also include file read, webshell upload, SSRF, and administrative bypasses. Many scripts provide interactive shells or allow arbitrary command execution, and some require authentication. The repository includes both proof-of-concept (POC) and full exploit scripts, with detailed usage instructions embedded in the code and readme files. The attack vector is predominantly network-based, targeting HTTP(S) endpoints, and the scripts are suitable for both vulnerability validation and exploitation. The codebase is mature, with operational exploits for each vulnerability, and is a valuable resource for penetration testers and red teamers.

zhzykerDisclosed Apr 1, 2020pythonjavanetwork
CodeTestMaturityPoCVerified exploit

This repository is a comprehensive Python-based exploit and POC framework with a GUI (Tkinter) for managing and executing a wide range of vulnerability checks and exploits. The structure is organized into EXP/ (exploit) and POC/ (proof-of-concept or auxiliary) directories, each containing scripts for specific products and vulnerabilities. The main entry point is CodeTest.pyw, which provides a GUI for selecting and running exploits. The EXP/ directory contains modules for major enterprise software (Apache, Jenkins, Nexus, JBoss, Drupal, ThinkPHP, Fastjson, etc.), each supporting multiple CVEs, primarily focused on remote code execution, file upload, and information disclosure vulnerabilities. The framework supports both detection and exploitation, with payloads that can be customized per target. The code is modular, with each exploit script implementing a class for the target product and methods for each CVE. The repository also includes auxiliary scripts for reconnaissance (e.g., FOFA, GithubHunter, JSFinder, LinkFinder) and configuration files. The overall purpose is to provide penetration testers and security researchers with a unified, extensible platform for vulnerability assessment and exploitation across a wide range of popular enterprise software.

adm1inDisclosed Dec 30, 2020pythonnetworkweb
weblogicPocMaturityPoCVerified exploit

This repository provides operational exploits for three Oracle WebLogic Server vulnerabilities: CVE-2020-2551, CVE-2020-2555, and CVE-2020-2883. The structure includes a Java-based exploit for CVE-2020-2551 (in CVE-2020-2551/src/exp.java) and two Python scripts for CVE-2020-2555 and CVE-2020-2883 (in CVE-2020-2555/CVE20202555Exp.py and CVE-2020-2883/CVE20202883Exp.py). The Java exploit leverages IIOP deserialization to trigger command execution, using callback domains (win.wb2551.starsosectest.starso.cn, lin.wb2551.starsosectest.starso.cn) to verify success. The Python scripts exploit the T3 protocol to send serialized payloads that execute arbitrary commands on the target. The exploits are configurable, allowing the attacker to specify the target URL and command to execute. The repository is well-structured, with clear separation for each CVE and supporting build files for the Java exploit. The main purpose is to provide proof-of-concept and operational exploit code for remote command execution on vulnerable WebLogic servers.

zzwlpxDisclosed May 16, 2020javapythonnetwork
cve-2020-2555MaturityPoCVerified exploit

This repository is a proof-of-concept (POC) exploit for CVE-2020-2555, a deserialization vulnerability in Oracle WebLogic Server. The main code is in 'src/com/axin/Main.java', which constructs a malicious Java object chain using classes from the Coherence library and Java's BadAttributeValueExpException. The exploit generates a serialized payload ('payload.ser') that, when deserialized by a vulnerable WebLogic server (typically via the T3 protocol), will execute 'calc.exe' on the target system, demonstrating arbitrary command execution. The repository contains mostly IDE configuration files and a single Java source file implementing the exploit logic. The exploit does not include code to send the payload over the network; it only generates the payload file, which must be delivered to the target by other means (e.g., using a separate tool or script).

MaskheDisclosed Mar 10, 2020javanetwork
CVE-2020-2555MaturityPoCVerified exploit

This repository provides a full exploit chain for CVE-2020-2555, a deserialization vulnerability in Oracle WebLogic Server (Coherence integration). The exploit consists of both a Python script (CVE-2020-2555.py) for network delivery and a comprehensive Java codebase for payload generation and advanced exploitation. The Java code constructs malicious serialized objects using known gadget chains (BadAttributeValueExpException, ChainedExtractor, ReflectionExtractor, LimitFilter) to achieve remote code execution. The exploit can install a persistent RMI backdoor ('supeream'), execute arbitrary commands, upload files, and uninstall the backdoor. The Python script sends the payload over the T3 protocol to the target WebLogic server. The codebase is modular, with clear separation between payload generation, protocol handling, and auxiliary functions (file upload, SSL, etc.). The exploit is operational and can be used for both one-shot command execution and persistent access. No authentication is required, and the attack is performed over the network via the T3/T3S protocol (default port 7001).

wsfengfanDisclosed Mar 6, 2020pythonjavanetwork
CVE-2020-2555MaturityPoCVerified exploit

This repository is a full-featured exploit for CVE-2020-2555, a remote code execution vulnerability in Oracle WebLogic Server via a deserialization bug in the Coherence component. The exploit is implemented primarily in Java, with a supporting Python script (weblogic_t3.py) for payload delivery. The Java code constructs a malicious serialized object using a gadget chain involving BadAttributeValueExpException and Coherence's ReflectionExtractor, ultimately leading to arbitrary command execution via Runtime.getRuntime().exec(). The main entry points are: - src/com/supeream/CVE_2020_2555.java: Demonstrates the exploit chain and sends the payload to a target WebLogic server using the T3 protocol. - src/com/supeream/Main.java: Provides a command-line interface for exploiting the vulnerability, supporting features such as command execution, file upload, and installation of a persistent RMI backdoor for further access. - src/com/supeream/payload/RemoteImpl.java: Implements the RMI backdoor, allowing remote command execution and file upload. - weblogic_t3.py: A Python script for sending serialized payloads to the T3 endpoint of a WebLogic server. The exploit requires the target to be running a vulnerable version of WebLogic (tested on 12.2.1.4, JDK 8u202, CentOS) without a security manager, and with a matching coherence.jar. The exploit can be used to execute arbitrary commands, upload files, and maintain persistent access via RMI. Several hardcoded IP addresses and endpoints are present for demonstration, but these can be customized for real-world use. The attack vector is network-based, targeting the T3/T3S protocol endpoints exposed by WebLogic.

Y4erDisclosed Mar 7, 2020javapythonnetwork
EXPOSURE SURFACE

Affected products & vendors

Products and vendors Mallory has correlated with this vulnerability. Open in Mallory to drill down to specific CPE configurations and version ranges.

VendorProductType
OracleAccess Managerapplication
OracleCoherenceapplication
OracleCommerce Platformapplication
OracleCommunications Diameter Signaling Routerapplication
OracleHealthcare Data Repositoryapplication
OracleRapid Planningapplication
OracleRetail Assortment Planningapplication
OracleUtilities Frameworkapplication
OracleWebcenter Portalapplication

Vendor-confirmed product mapping. Mallory continuously reconciles this list against your asset inventory.

What this page doesn’t show

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This page is what’s public. Mallory adds the parts that aren’t: which of your assets are affected, which adversaries are exploiting it right now, which detections to deploy, and what to do tonight.
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Threat actor evidence

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Associated malware1

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Detection signatures1

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Vendor-by-vendor mapping

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Social activity

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