Unauthenticated Remote Code Execution via EAP CDR Unmarshalling

when EAP runs with -secmgr, the openjdk-orb's JDKBridge honours attacker-supplied CDR codebase URLs during object unmarshalling on :3528, allowing an unauthenticated attacker to load and instantiate arbitrary classes from a remote URL in the server JVM before EJB security interceptors run.

Casky was already ahead

This CVE exploits attack patterns that Casky's 446matched skills already investigate — long before this vulnerability was disclosed. Claude's reasoning model maps these techniques to MITRE ATT&CK, so practitioners who ran these skills have already seen the threat behaviour in their findings.

Analysis

CVE-2026-15560 represents a critical pre-authentication remote code execution vulnerability in JBoss EAP when running with the security manager enabled. The flaw exists in OpenJDK ORB's JDKBridge component, which improperly validates Common Data Representation (CDR) codebase URLs during Java object deserialization on port 3528. An unauthenticated attacker can exploit this by supplying malicious CDR URLs, forcing the server to load and instantiate arbitrary classes from attacker-controlled remote sources before EJB security interceptors can intervene. This is particularly dangerous because it bypasses authentication entirely and executes with the privileges of the EAP process, affecting any organization running vulnerable EAP instances exposed to untrusted networks.

Casky's 446 mapped skills leverage Claude's extended reasoning to detect the attack chain across MITRE ATT&CK techniques TA0001 (Reconnaissance), TA0043 (Resource Development), and TA0002 (Execution). Practitioners using Casky would observe detection patterns including: (1) unusual outbound connections to non-standard ports attempting to fetch serialized Java objects or class definitions (TA0001/TA0043 - Initial Access preparation), (2) anomalous CDR protocol traffic on port 3528 containing suspicious codebase parameters, (3) ClassNotFoundException errors or unexpected class loading events followed by remote code execution artifacts, and (4) process spawning or system command execution originating from the EAP JVM without corresponding user authentication events. The platform's security skills would correlate these indicators to surface the exploitation attempt before arbitrary code achieves persistence or lateral movement.

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Casky Risk Score

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EPSS Probability

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Shodan Exposure

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GreyNoise Signal

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Composite risk scoring from EPSS, CISA KEV, Shodan, and GreyNoise — 21 security APIs correlated into a single Casky Risk Score. Coming in Casky Pro. Join early access →

446 Casky skills cover this attack pattern

These skills use Claude AI's reasoning model to surface findings in the same attack categories as CVE-2026-15560.

Abuse of Public-Facing API: Mobile API Abuse

mobile security · low

Run

abusing-dpapi-for-credential-access

red teaming · high

Run

abusing-shadow-credentials-for-privesc

red teaming · high

Run

MITRE ATT&CK Techniques

TA0001 TA0043 TA0002

Investigate the attack patterns behind CVE-2026-15560

Casky has 446 skills that investigate the attack patterns behind CVE-2026-15560. Run one and get CVSS-scored findings in 3 minutes.

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