CVE-2026-21925Network attack vector

Unauthenticated data disclosure and modification

Published Jan 20, 2026 · Updated Jan 20, 2026

An RMI vulnerability in affected Oracle Java SE and GraalVM releases allows remote attackers to read and modify accessible data. Oracle has not published the faulty RMI class, method, or input-handling operation; it states only that component APIs can receive supplied data through services. Exploitation is unauthenticated but high-complexity and requires network API exposure or untrusted code in a sandboxed client, with access limited to some writable data and a readable subset.

CVSS severity4.8
Medium
EPSS probability0.22%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

An RMI vulnerability in affected Oracle Java SE and GraalVM releases allows remote attackers to read and modify accessible data. Oracle has not published the faulty RMI class, method, or input-handling operation; it states only that component APIs can receive supplied data through services. Exploitation is unauthenticated but high-complexity and requires network API exposure or untrusted code in a sandboxed client, with access limited to some writable data and a readable subset.

The record

CVE
CVE-2026-21925
Published
Jan 20, 2026
Updated
Jan 20, 2026
Vendor
Oracle
Product
Oracle GraalVM Enterprise Edition
Classifications
T1190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jan 20, 2026CVE publishedPublication date reported by the CVE source.
  2. Jan 20, 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.

  1. Affected versionversion=21.3.16

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Oracle · Oracle GraalVM Enterprise Editionversion=21.3.16
Oracle · Oracle GraalVM for JDKversion=17.0.17; version=21.0.9
Oracle · Java Platform, Standard Edition (Java SE)version=11.0.29; version=17.0.17; version=21.0.9; version=25.0.1; version=8u471; version=8u471-b50; version=8u471-perf

Published CVSS scores

4.8OracleCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N

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.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

T1190Exploit Public-Facing Application

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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