dbcve.org
Actively exploited in the wild. This CVE is on the CISA Known Exploited Vulnerabilities list — treat remediation as urgent. Federal remediation due by 22 May 2023.
Weblogic ServerApplication · Oracle

CVE-2023-21839

HIGH · 7.5 CVSS v3.1 Published 2023-01-18
Patch available
A vendor patch is available. No clean upgrade release — apply the published patch.
See remediation →
100/100
Remediation priority · Urgent
In the wild High EPSS Public exploit Remotely reachable No privileges Zero-click Patch available

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
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, IIOP 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).

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · high confidence

Oracle WebLogic Server contains a deserialization vulnerability in its Core component that allows unauthenticated attackers with network access via T3 or IIOP protocols to achieve remote code execution or unauthorized access to sensitive data. The vulnerability affects versions 12.2.1.3.0, 12.2.1.4.0, and 14.1.1.0.0.

MitigationApply Oracle Critical Patch Update for CVE-2023-21839. Additionally, restrict or disable T3/IIOP protocol access at the network level if not required, and enforce network segmentation to limit exposure.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
Weblogic ServerApplication
Affected:= 12.2.1.3.0= 12.2.1.4.0= 14.1.1.0.0

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
None
Availability
None

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

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Identify WebLogic Server version
    Locate the WebLogic installation and check the version. In the WebLogic Admin Console, navigate to 'Version' under 'Domain' or check the inventory file (inventory.xml) in the Oracle home directory. Alternatively, check the manifest file in the WebLogic lib directory or run 'java -jar weblogic.jar' to display version information.
    Affected if The installed version matches exactly 12.2.1.3.0, 12.2.1.4.0, or 14.1.1.0.0. If your version is different, you are not affected by this specific CVE.
  2. Confirm T3 protocol is enabled
    In the WebLogic Admin Console, go to 'Servers' > 'Server Name' > 'Protocols' > 'General'. Check if 'Enable T3' is checked. Alternatively, review the server's config.xml file for the <t3-enabled>true</t3-enabled> setting under the server configuration.
    Affected if T3 protocol is enabled on the affected WebLogic Server version. Note the default T3 port is 7001 (admin) or 7002 (managed).
  3. Confirm IIOP protocol is enabled
    In the WebLogic Admin Console, go to 'Servers' > 'Server Name' > 'Protocols' > 'IIOP'. Check if 'Enable IIOP' is checked. Alternatively, review the config.xml for <iiop-enabled>true</iiop-enabled> setting.
    Affected if IIOP protocol is enabled on the affected WebLogic Server version. The default IIOP port is typically 7001 for the admin server.
  4. Verify network exposure of T3/IIOP ports
    Check your firewall rules, load balancer configurations, and security groups to determine if ports 7001, 7002, or any custom T3/IIOP ports are accessible from untrusted networks. Run 'netstat -an' or 'ss -tuln' on the WebLogic host to list all listening ports.
    Affected if T3 or IIOP ports are exposed to the internet or untrusted networks without network-level filtering. Even if protocols are enabled, restricted network access may limit exploitability.

You are affected if your WebLogic Server version is exactly 12.2.1.3.0, 12.2.1.4.0, or 14.1.1.0.0 AND either T3 or IIOP protocol is enabled AND these ports are network-accessible from an untrusted source.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

dbcve · scoped
Patch available Apply the vendor patch
Vendor patch www.oracle.com →
Interim mitigation

Apply Oracle Critical Patch Update for CVE-2023-21839. Additionally, restrict or disable T3/IIOP protocol access at the network level if not required, and enforce network segmentation to limit exposure.

Recommended fix High confidence

Oracle WebLogic Server 12.2.1.3.0, 12.2.1.4.0, and 14.1.1.0.0 with January 2023 CPU补丁 applied, or upgrade to latest supported Oracle WebLogic Server version with latest CPU

  1. Apply Oracle Critical Patch Update January 2023 which includes the fix for CVE-2023-21839
  2. Ensure WebLogic Server is updated to a version that includes the security patch for this vulnerability
  3. After applying the patch, verify that T3/IIOP protocols are properly secured or restricted if not required
  4. Consider network segmentation to limit exposure of the T3 and IIOP listeners to only trusted sources
  5. Validate the fix by confirming the WebLogic Server starts without errors and the vulnerability is no longer exploitable
Caveat Review Oracle Critical Patch Update January 2023 patch notes for any known issues or compatibility concerns before applying to production systems

Generated from the published advisory — verify against the referenced sources before acting.

Fix this in Weblogic Server Exploited in the wild — priority engagement
  • Consultation4.0 h
  • Implementation4.0 h
  • Testing8.0 h
  • Review / QA4.0 h
20.0 hours of engineering $3,440
Get it fixed fast

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $5,504.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2023-21839 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.

Get it on GitHub Scan in the browser

References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2023-21839 in production — separate from our analysis above.

No notes yet

Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.

What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data