Attack ChainAIDerived
Hypothetical attack flow derived from CVE metadata – not a confirmed exploit chain
-
AccessReach network-exposed JGSS/GSS-API endpoint
-
ExploitSupply crafted data to the API via a network protocol
-
ExecutionTrigger integrity flaw under required conditions
-
ImpactCreate, modify, or delete critical data
Vulnerability Assessment
| Weakness |
CWE
OWASP Top 10:2025
A01:2025 - Broken Access Control
ASVS 5.0
V8 - Authorization Access control enforcement
MITRE ATT&CK
1 technique across 1 tactic: Defense Evasion The technique list with ATT&CK links and the kill-chain view is part of the Basic plan and up. |
| Exploitation Conditions | Exploitation requires an application or service that feeds attacker-supplied data into the Java JGSS (GSS-API/Kerberos) component over the network - Oracle explicitly notes it is triggered by supplying data to APIs in the component (e.g., through a web service), NOT via Untrusted Java Web Start applications or Untrusted applets. Limiting factors: high attack complexity (AC:H) means the attacker needs specific, non-trivial conditions to succeed; the deployed application must actually expose JGSS data-processing to untrusted network input; and impact is confined to data integrity (no data disclosure, no denial of service). Default JVMs that do not expose JGSS APIs to untrusted remote data are not reachable by this vector. |
| Impact | This is a moderate-severity integrity flaw (CVSS 3.1 base 5.9) in the JGSS component of Oracle Java SE, GraalVM for JDK, and GraalVM Enterprise Edition. The CVSS vector (AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N) signals a network-reachable, unauthenticated issue requiring no user interaction, but with high attack complexity (AC:H) and impact limited strictly to integrity (I:H; C:N, A:N). No EPSS score, CISA KEV listing, or POC was provided in the input, and no public exploit is identified at time of analysis - so the only exploitation signals are the raw CVSS metrics, which point to a difficult-to-exploit weakness rather than a mass-exploitation candidate. The AC:H rating materially lowers real-world urgency despite the unauthenticated network vector: exploitation likely demands specific conditions, timing, or data-shaping to succeed. The 'Authentication Bypass' tag is in tension with the CVSS, which models a pure integrity (I:H) impact and no scope change, not a privilege/authentication escalation - verify the precise weakness against Oracle's advisory, as the tag may be imprecise. Net assessment: patch on the normal Oracle quarterly cadence; this is a real but lower-tier priority (high prevalence of Java, offset by high exploit complexity and no confirmed exploitation or POC), not an emergency. |
| Exploit ScenarioDerived | An application exposes Java JGSS/GSS-API processing of attacker-controlled data over the network (for example via a web service), and a remote unauthenticated attacker submits specially crafted data to that API. Because high attack complexity applies, the attacker must satisfy specific preconditions, but a successful attack lets them create, delete, or modify critical data without touching confidentiality or availability. No public exploit code is identified at time of analysis, so this remains a theoretical-but-credible network attack. |
Get an e-mail when this CVE is exploited, patched or re-scored. Free account.
Alert meAnalysisAIv1 – Oct 21, 2026
Unauthorized modification of critical data in Oracle Java SE's JGSS component affects Java SE 8u503, 11.0.32.1, 17.0.20.1, 21.0.12.1, 25.0.4.1, and 27, as well as GraalVM for JDK 17.0.20.1/21.0.12.1 and GraalVM Enterprise Edition 21.3.19.1.1, allowing a remote, unauthenticated attacker to alter data accessible through the JVM. The flaw is difficult to exploit (CVSS 3.1 base 5.9, AC:H) and requires an application or web service that supplies attacker-controlled network data to JGSS APIs; Oracle states it is not reachable through untrusted Java Web Start applications or applets. No public exploit identified at time of analysis and no CISA KEV active exploitation is confirmed, with impact limited to integrity and no confidentiality or availability effect.
RemediationAI
Apply the Oracle Critical Patch Update (CPU) October 2026 fixes for the affected Java SE and GraalVM builds; the vendor advisory at https://www.oracle.com/security-alerts/cpuoct2026.html provides the exact patched builds for each listed version because the input data does not specify individual fix version numbers. Patch status: patch available per vendor advisory. Until patching is complete, reduce exposure by restricting network access to applications and web services that pass untrusted data into JGSS APIs - for example, limiting JGSS/Kerberos/SPNEGO token-processing endpoints to trusted clients or internal networks - but this breaks legitimate cross-network SSO and Kerberos authentication. Where JGSS is not required, disabling or not enabling Kerberos/SPNEGO processing in the JVM or application removes the attack surface, at the cost of losing those authentication features. Add strict input validation and size limits on GSS-API tokens at the application layer as a defense-in-depth measure, recognizing that this may not fully prevent the flaw and can reject malformed but legitimate tokens. Default JVMs that do not expose JGSS APIs to untrusted remote input are not reachable by this vector, so prioritizing internet-facing services that process GSS tokens is appropriate. No public exploit identified at time of analysis and no CISA KEV active exploitation is confirmed.
Affected VersionsENISA
Affected Packages
Source: OSV (Open Source Vulnerabilities)
Affects your stack
Affects 3 packages in euvd
Checking this CVE against your own stacks and servers is part of the Basic plan and up.
Technical ContextAI · show details
JGSS is Oracle's implementation of the Java Generic Security Services (GSS-API) framework, commonly used for Kerberos and SPNEGO authentication in Java applications and web services. The vulnerability is an input-handling weakness in JGSS that lets data supplied to the component's APIs cause unauthorized creation, deletion, or modification of data reachable by the JVM; Oracle did not assign a CWE. Because the CVSS vector is AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N, the issue is remotely reachable without credentials or user interaction but requires non-trivial conditions, and it affects only integrity. The attack surface is applications that accept untrusted network input and pass it into JGSS processing - for example, services that parse GSS-API or Kerberos tokens - rather than default JVMs that do not expose those APIs to remote data. Affected builds span Oracle Java SE 8u503/8u503-perf, 11.0.32.1, 17.0.20.1, 21.0.12.1, 25.0.4.1, and 27; GraalVM for JDK 17.0.20.1 and 21.0.12.1; and GraalVM Enterprise Edition 21.3.19.1.1. The Oracle CPU October 2026 advisory is the authoritative source.
Know when Java gets its next vulnerability
- Watch products and get an email when something new is published
- Check this CVE against your own stack and servers
- Exploit and PoC references, threat intelligence from 22 sources
No credit card · 7-day full trial
Severity by source
AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N
Network-reachable unauthenticated data supplied to JGSS APIs (AV:N/PR:N/UI:N) but needing specific conditions (AC:H); impact is integrity-only (I:H, C:N/A:N) within one component (S:U).
Primary rating from Vendor (oracle).
CVSS VectorVendor: oracle
DescriptionCVE.org
Vulnerability in the Oracle Java SE, Oracle GraalVM for JDK, Oracle GraalVM Enterprise Edition product of Oracle Java SE (component: JGSS). Supported versions that are affected are Oracle Java SE: 8u503, 8u503-perf, 11.0.32.1, 17.0.20.1, 21.0.12.1, 25.0.4.1, 27; Oracle GraalVM for JDK: 17.0.20.1 and 21.0.12.1; Oracle GraalVM Enterprise Edition: 21.3.19.1.1. Difficult to exploit vulnerability allows unauthenticated attacker with network access via multiple protocols to compromise Oracle Java SE, Oracle GraalVM for JDK, Oracle GraalVM Enterprise Edition. Successful attacks of this vulnerability can result in unauthorized creation, deletion or modification access to critical data or all Oracle Java SE, Oracle GraalVM for JDK, Oracle GraalVM Enterprise Edition accessible data. Note: This vulnerability can only be exploited by supplying data to APIs in the specified Component without using Untrusted Java Web Start applications or Untrusted Java applets, such as through a web service. CVSS 3.1 Base Score 5.9 (Integrity impacts). CVSS Vector: (CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N).
Threat Intelligence Overview
How this decision was reached
The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.
What every action level means
SSVC AssessmentENISA
Priority Score
Attack Technique
Authentication bypass attacks exploit flaws in the verification mechanisms that control access to systems and applications.
Oracle Java SE 7 Update 6 and earlier contains multiple sandbox bypass vulnerabilities via the ClassFinder and forName m
Remote code execution in IBM Sterling B2B Integrator, Sterling Integrator, and Tivoli Common Reporting allows unauthenti
Java Runtime Environment sandbox bypass via incorrect image channel verification in 2D component allows remote unauthent
Oracle Java SE JDK/JRE 7 and 6 Update 27 and earlier allows remote code execution with complete system compromise throug
JBoss Seam 2 in Red Hat JBoss EAP 4.3.0 fails to sanitize JBoss Expression Language inputs, allowing remote attackers to
Unspecified vulnerability in the Java Runtime Environment (JRE) component in Oracle Java SE 7 update 4 and earlier, 6 up
Multiple vulnerabilities in Oracle Java 7 before Update 11 allow remote attackers to execute arbitrary code by (1) using
Unspecified vulnerability in the Java Runtime Environment (JRE) component in Oracle Java SE 7 Update 2 and earlier, 6 Up
The WLS Security component in Oracle WebLogic Server 10.3.6.0, 12.1.2.0, 12.1.3.0, and 12.2.1.0 allows remote attackers
Unspecified vulnerability in the Java Runtime Environment (JRE) component in Oracle Java SE 7 Update 7 and earlier allow
Remote unauthenticated attackers can execute arbitrary code on Adobe ColdFusion servers through Java deserialization fla
The ExceptionDelegator component in Apache Struts before 2.2.3.1 interprets parameter values as OGNL expressions during
EUVD-2026-106710
GHSA-g364-xwwc-5hvh
NVD
CVE.org
EPSS
Exploit-DB