`CVE-2023-21830` Oracle Java SE

Affected software	Oracle Java SE
Affected versions	Oracle Java SE: 8u351, 8u351-perf; Oracle GraalVM Enterprise Edition: 20.3.8, 21.3.4
Severity	5.3 Medium CVSS 3.1
Fixed in	Oracle Critical Patch Update January 2023
Published	18 Jan 2023
Updated	17 Jun 2026

Description

Vulnerability in the Oracle Java SE, Oracle GraalVM Enterprise Edition product of Oracle Java SE (component: Serialization). Supported versions that are affected are Oracle Java SE: 8u351, 8u351-perf; Oracle GraalVM Enterprise Edition: 20.3.8 and 21.3.4. Easily exploitable vulnerability allows unauthenticated attacker with network access via multiple protocols to compromise Oracle Java SE, Oracle GraalVM Enterprise Edition. Successful attacks of this vulnerability can result in unauthorized update, insert or delete access to some of Oracle Java SE, Oracle GraalVM Enterprise Edition accessible data. Note: This vulnerability applies to Java deployments, typically in clients running sandboxed Java Web Start applications or sandboxed Java applets, that load and run untrusted code (e.g., code that comes from the internet) and rely on the Java sandbox for security. This vulnerability does not apply to Java deployments, typically in servers, that load and run only trusted code (e.g., code installed by an administrator). CVSS 3.1 Base Score 5.3 (Integrity impacts). CVSS Vector: (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N).

Exploitation status

No public exploit

No exploit has been reported in the sources we check. Published 3 years ago.

CISA KEV not listed
VulnCheck KEV not listed
CISA Vulnrichment exploitation: none
Indexed PoC none indexed
EPSS 1.1% chance in 30 days

Waratek protection

Protected by Waratek

Waratek has a rule that blocks attacks on this vulnerability.

Protection full
Action available patch rule
Review human ARMR file
Record active

Decided by	An ARMR patch file on disk for this CVE
Finding	CVE has an ARMR patch rule that provides mitigation

Decided by

An ARMR patch file on disk for this CVE

Finding

CVE has an ARMR patch rule that provides mitigation

ARMR rule files

1 file

The rule files Waratek ships for this CVE. Some CVEs need more than one, for example one per affected library or one per ARMR version.

CVE-2023-21830.armr patch rule, ARMR 2.6 added 2023-02-23 updated 2026-03-04

How to mitigate CVE-2023-21830

Apply the fix in Oracle Critical Patch Update January 2023. Until you can, Waratek RASP blocks exploitation with a rule written for this CVE. It runs inside the Java application, with no code changes.

Waratek RASP Runtime protection for Java applications

Affected software and releases

Oracle advisories

Advisory	Type	Quarter	Products Oracle names in its risk matrix
Oracle Critical Patch Update July 2023 ↗	CPU	2023-Q3	Oracle Communications Applications / Core (Oracle Java SE) (5.5.0-5.5.17, 6.0.0-6.0.2)
Oracle Critical Patch Update January 2023 ↗	CPU	2023-Q1	Oracle Java SE / Serialization (Oracle Java SE: 8u351, 8u351-perf; Oracle GraalVM Enterprise Edition: 20.3.8, 21.3.4) Oracle's note: This vulnerability applies to Java deployments, typically in clients running sandboxed Java Web Start applications or sandboxed Java applets, that load and run untrusted code (e.g., code that comes from the internet) and rely on the Java sandbox for security. This vulnerability can also be exploited by using APIs in the specified Component, e.g., through a web service which supplies data to the APIs.

Advisory

Type

Quarter

Products Oracle names in its risk matrix

Oracle Critical Patch Update July 2023 ↗

CPU

2023-Q3

Oracle Communications Applications / Core (Oracle Java SE) (5.5.0-5.5.17, 6.0.0-6.0.2)

Oracle Critical Patch Update January 2023 ↗

CPU

2023-Q1

Oracle Java SE / Serialization (Oracle Java SE: 8u351, 8u351-perf; Oracle GraalVM Enterprise Edition: 20.3.8, 21.3.4)
Oracle's note: This vulnerability applies to Java deployments, typically in clients running sandboxed Java Web Start applications or sandboxed Java applets, that load and run untrusted code (e.g., code that comes from the internet) and rely on the Java sandbox for security. This vulnerability can also be exploited by using APIs in the specified Component, e.g., through a web service which supplies data to the APIs.

Oracle components and versions

Family	Component	Versions, as Oracle lists them	Read as
Oracle Communications Applications	Core (Oracle Java SE)	5.5.0-5.5.17, 6.0.0-6.0.2
Oracle Java SE	Serialization	Oracle Java SE: 8u351, 8u351-perf; Oracle GraalVM Enterprise Edition: 20.3.8, 21.3.4	8.0.351.0 · 20.3.8.0 · 21.3.4.0

Family

Component

Versions, as Oracle lists them

Read as

Oracle Communications Applications

Core (Oracle Java SE)

5.5.0-5.5.17, 6.0.0-6.0.2

Oracle Java SE

Serialization

Oracle Java SE: 8u351, 8u351-perf; Oracle GraalVM Enterprise Edition: 20.3.8, 21.3.4

8.0.351.0 · 20.3.8.0 · 21.3.4.0

Products and versions

5 products, 16 version entries

Source	Vendor	Product	Scheme	Affected versions
nvd	azul	zulu	generic	6.51 · 7.57 · 8.66
nvd	oracle	communications unified assurance	generic	≥ 5.5.0 and ≤ 5.5.17 · ≥ 6.0.0 and ≤ 6.0.2
nvd	oracle	graalvm	javase	20.3.8 · 21.3.4 · 22.3.0
nvd	oracle	jdk	javase	1.8.0:update351 · 11.0.17 · 17.0.5 · 19.0.1
nvd	oracle	jre	javase	1.8.0:update351 · 11.0.17 · 17.0.5 · 19.0.1

Source

Vendor

Product

Scheme

Affected versions

nvd

azul

zulu

generic

6.51 · 7.57 · 8.66

nvd

oracle

communications unified assurance

generic

≥ 5.5.0 and ≤ 5.5.17 · ≥ 6.0.0 and ≤ 6.0.2

nvd

oracle

graalvm

javase

20.3.8 · 21.3.4 · 22.3.0

nvd

oracle

jdk

javase

1.8.0:update351 · 11.0.17 · 17.0.5 · 19.0.1

nvd

oracle

jre

javase

1.8.0:update351 · 11.0.17 · 17.0.5 · 19.0.1

References

URL	Tags
https://access.redhat.com/errata/RHSA-2023:0203	ADVISORY, RHSA-2023:0203
https://access.redhat.com/security/cve/CVE-2023-21830	REPORT, RHSA-2023:0203
https://access.redhat.com/errata/RHSA-2023:0204	ADVISORY, RHSA-2023:0204
https://access.redhat.com/errata/RHSA-2023:0205	ADVISORY, RHSA-2023:0205
https://access.redhat.com/errata/RHSA-2023:0206	ADVISORY, RHSA-2023:0206
https://access.redhat.com/errata/RHSA-2023:0207	ADVISORY, RHSA-2023:0207
https://access.redhat.com/errata/RHSA-2023:0208	ADVISORY, RHSA-2023:0208
https://access.redhat.com/errata/RHSA-2023:0209	ADVISORY, RHSA-2023:0209
https://bugzilla.redhat.com/show_bug.cgi?id=2160490	REPORT, RHSA-2023:0209
https://access.redhat.com/errata/RHSA-2023:0210	ADVISORY, RHSA-2023:0210

URL

Timeline

Published	2023-01-18	By the CVE Program.
ARMR remediation created	2023-02-23	Earliest commit adding this CVE's ARMR patch or security rule.
ARMR remediation last updated	2026-03-04	Most recent commit touching this CVE's ARMR patch or security rule.
Last VRT activity	2026-03-04	Most recent commit touching this CVE's classification, patch or rule file.
NVD record modified	2026-06-17	NVD's own last-modified date for this record.

Published

2023-01-18

By the CVE Program.

ARMR remediation created

2023-02-23

Earliest commit adding this CVE's ARMR patch or security rule.

ARMR remediation last updated

2026-03-04

Most recent commit touching this CVE's ARMR patch or security rule.

Last VRT activity

2026-03-04

Most recent commit touching this CVE's classification, patch or rule file.

NVD record modified

2026-06-17

NVD's own last-modified date for this record.

How VRT decided (2 of 24 rules ran)

2 of 24 rules ran. The rest didn't run because an earlier rule had already settled the CVE.

# Rule Outcome Status Detail

identity: Does this identifier describe a vulnerability at all? the first rule that matches decides

1 rejected no match CVE Program withdrawal of this identifier

scope: Is it a vulnerability Waratek protects? the first rule that matches decides

2 armr-patch-file decided it matched Protected by Waratek ARMR patch file exists for this CVE

3 armr-secure-rule-file not reached An ARMR security-rule template on disk for this CVE

4 manual-classification not reached A researcher's recorded decision for this specific CVE

5 manual classification not reached Manual classification of this CVE in the legacy dataset

6 non-java-upstream not reached A root cause in non-Java code: an OS kernel, a C library, or a bundled runtime

7 oracle-component not reached The defect being in a component of a tracked product the agent does not reach: JavaFX, the Java SE installer, the JInitiator browser plug-in, the native WebLogic proxy plug-in, or a native part of Oracle Application Server or Collaboration Suite (HTTP Server, Web Cache, Internet Directory, mail and calendar servers). Oracle gives these no CPE of their own and names them only in the description.

8 java-client-side not reached Oracle's own risk-matrix note saying the CVE is reached only through untrusted code in the Java sandbox (applets, Web Start) or only through a client installation of Java, so a server running its own trusted code is not exposed

9 osv-maven not reached An OSV.dev record of this CVE affecting a package published to Maven Central. When every such package is one business applications do not use (Minecraft mods and launchers, Fastjson) and no tracked product is named by CPE, it settles the CVE as Outside Waratek scope instead

10 cna-maven-package not reached An affected Maven artifact named by the CNA itself

11 known-cpe-product not reached An NVD CPE naming a product ARMR tracks

12 cna-cpe-product not reached A CPE the CNA published naming a tracked product. Oracle publishes these on advisory day, months before NVD.

13 oracle-advisory-family not reached A tracked product family named in Oracle's own risk matrix. CPE cannot carry a suite name, only a module.

14 cna-named-product not reached A tracked product named in words by the CVE's own CNA, on a record with no CPE yet. Apache and Eclipse publish these on advisory day, before NVD adds CPE data.

15 non-deployable-product not reached The only affected product being a sealed appliance image, where Java runs but no -javaagent can be attached

16 unmatched-product not reached No tracked product matched above, and none present at all

disposition: What do we do about one that is? every rule runs

17 patch-hint not reached A reference pointing at the upstream fix: a commit, a PR, a Red Hat bug

18 open-source-maven not reached The affected package being open source on Maven, so the fix can be read

19 poc-derivable not reached An indexed exploit clearing the evidence bar to reverse-engineer, where there is no source to read

20 no-exploit not reached Nothing to build a rule from yet: no published exploit, no CISA record of exploitation and no source-level change to read

21 secure-rule-match not reached A vulnerability class already blocked by an ARMR security rule

22 exploited-no-fix-or-poc not reached Somebody exploiting this CVE (a CISA or VulnCheck KEV listing, or a CISA verdict of active exploitation), with no fix, source code or PoC to build a rule from

23 below-action-threshold not reached Medium or Low severity, no CISA or VulnCheck KEV listing, no PoC clearing the evidence bar, no CISA verdict, no Oracle advisory

24 no-exploit-published not reached Exploit code for this candidate, published in a reviewed catalogue or a GitHub repository with 5 or more stars, or in use per CISA or VulnCheck; not only a CISA verdict, a forecast, or nothing at all

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