`CVE-2023-21931` Oracle WebLogic Server

Affected software	Oracle WebLogic Server
Affected versions	12.2.1.3.0, 12.2.1.4.0, 14.1.1.0.0
Severity	7.5 High CVSS 3.1
Fixed in	Oracle Critical Patch Update April 2023
Weakness	Missing authentication (CWE-306)
Published	18 Apr 2023
Updated	13 Nov 2026

Description

Vulnerability in the Oracle WebLogic Server product of Oracle Fusion Middleware (component: Core). Supported versions that are affected are 12.2.1.3.0, 12.2.1.4.0 and 14.1.1.0.0. Easily exploitable vulnerability allows unauthenticated attacker with network access via T3 to compromise Oracle WebLogic Server. Successful attacks of this vulnerability can result in unauthorized access to critical data or complete access to all Oracle WebLogic Server accessible data. CVSS 3.1 Base Score 7.5 (Confidentiality impacts). CVSS Vector: (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N).

Exploitation status

Forecast only (82% 30-day chance)

No exploit has been reported in the sources we check. EPSS puts this CVE in the top 0.33% of all scored CVEs. That is a model's forecast, not a report of exploitation.

CISA KEV not listed
VulnCheck KEV not listed
CISA Vulnrichment exploitation: none
Indexed PoC none indexed
EPSS 82% chance in 30 days A model's forecast, not a report of exploitation. Higher than 99.7% of all scored CVEs.

Waratek protection

Protected by Waratek

Waratek has a rule that blocks attacks on this vulnerability.

Protection full Deserialization
Action available security rule
Review human Researcher
Record active

Decided by	A researcher's recorded decision for this specific CVE
Finding	A researcher found this CVE protected by the ARMR Deserial Rule (DOS), Marshal rce rule.

Decided by

A researcher's recorded decision for this specific CVE

Finding

A researcher found this CVE protected by the ARMR Deserial Rule (DOS), Marshal rce rule.

Waratek research note

written 2026-11-13

Written by a Waratek engineer who reviewed this CVE. Their decision sets the status above, ahead of every automated rule except a withdrawal.

Comments

Rule Name: Deserial Rule (DOS), Marshal rce rule

How to mitigate CVE-2023-21931

Apply the fix in Oracle Critical Patch Update April 2023. Until you can, Waratek RASP blocks exploitation with its deserialization rule. 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 April 2023 ↗	CPU	2023-Q2	Oracle Fusion Middleware / Core (12.2.1.3.0, 12.2.1.4.0, 14.1.1.0.0)

Advisory

Type

Quarter

Products Oracle names in its risk matrix

Oracle Critical Patch Update April 2023 ↗

CPU

2023-Q2

Oracle Fusion Middleware / Core (12.2.1.3.0, 12.2.1.4.0, 14.1.1.0.0)

Oracle components and versions

Family	Component	Versions, as Oracle lists them	Read as
Oracle Fusion Middleware	Core	12.2.1.3.0, 12.2.1.4.0, 14.1.1.0.0	12.2.1.3.0 · 12.2.1.4.0 · 14.1.1.0.0

Family

Component

Versions, as Oracle lists them

Read as

Oracle Fusion Middleware

Core

12.2.1.3.0, 12.2.1.4.0, 14.1.1.0.0

12.2.1.3.0 · 12.2.1.4.0 · 14.1.1.0.0

Products and versions

1 product, 3 version entries

Source	Vendor	Product	Scheme	Affected versions
nvd	oracle	weblogic server	generic	12.2.1.3.0 · 12.2.1.4.0 · 14.1.1.0.0

Source

Vendor

Product

Scheme

Affected versions

nvd

oracle

weblogic server

generic

12.2.1.3.0 · 12.2.1.4.0 · 14.1.1.0.0

References

URL	Tags
http://packetstormsecurity.com/files/172882/Oracle-Weblogic-PreAuth-Remote-Command-Execution.html
https://www.oracle.com/security-alerts/cpuapr2023.html	Patch, Vendor Advisory

URL

Timeline

Published	2023-04-18	By the CVE Program.
NVD record modified	2026-06-17	NVD's own last-modified date for this record.
Classification created	2026-11-13	First commit adding this CVE's research note.
Last VRT activity	2026-11-13	Most recent commit touching this CVE's classification, patch or rule file.

Published

2023-04-18

By the CVE Program.

NVD record modified

2026-06-17

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

Classification created

2026-11-13

First commit adding this CVE's research note.

Last VRT activity

2026-11-13

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

How VRT decided (4 of 24 rules ran)

4 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 no match An ARMR patch file on disk for this CVE

3 armr-secure-rule-file no match An ARMR security-rule template on disk for this CVE

4 manual-classification decided it matched Protected by Waratek A researcher found this CVE protected by the ARMR Deserial Rule (DOS), Marshal rce rule.

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

NVD ↗ · CVE.org ↗