Exploited Hunt for compromise (CISA)

CVE-2026-21962

Oracle WebLogic Server · Web and application servers

Oracle HTTP Server and Oracle Weblogic Server Proxy Plug-in Improper Access Control Vulnerability

At a glance

Exploited. Added to CISA’s catalog of exploited vulnerabilities on August 24, 2026.

CISA asks you to hunt for signs of compromise: patching is not enough if the device has already been breached.

Affected product: Oracle WebLogic Server (category Web and application servers, indicative classification). Name in CISA’s catalog: Oracle HTTP Server and Oracle Weblogic Server Proxy Plug-in.

What should I do?

Apply the patches or mitigations from Oracle; if none are available, stop using the product. Start with internet-facing devices.

CISA also asks you to hunt for signs of compromise: patching is not enough if the device has already been breached.

Deadline set by CISA for US federal agencies: 3 days (due August 27, 2026). It only binds those agencies, but it is a useful measure of urgency.

Oracle security advisories page (general page, not the advisory for this vulnerability)
The vendor’s specific advisory is listed in the NVD references: CVE-2026-21962 on the NVD website.

Original text of the required action (CISA)

Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA's BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA's "Forensics Triage Requirements" (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.

Timeline

January 20, 2026 Vulnerability published Publication date (NVD)
August 24, 2026 Exploitation confirmed Added to CISA’s KEV catalog
August 27, 2026 CISA deadline Remediation deadline set for US federal agencies

The facts, with their sources

Exploitation confirmed: Yes, on August 24, 2026 Date added to the catalog of exploited vulnerabilities. Exploitation itself may have started earlier. Source: KEV catalog, collected September 29, 2026 at 14:57 UTC
Ransomware: No known use to date That does not guarantee it is not being used: the information is not public. Source: KEV catalog, collected September 29, 2026 at 14:57 UTC
Hunt for compromise: Requested by CISA Source: KEV catalog, collected September 29, 2026 at 14:57 UTC
CISA required action: Apply the patches or mitigations from Oracle; if none are available, stop using the product. Start with internet-facing devices. Rewritten by this site from CISA’s original text. Source: KEV catalog, collected September 29, 2026 at 14:57 UTC
CISA deadline: August 27, 2026, 3 days Set for US federal agencies: a measure of urgency, not an obligation elsewhere. Source: KEV catalog, collected September 29, 2026 at 14:57 UTC
Vulnerability published: January 20, 2026 Source: National Vulnerability Database (NVD), collected September 29, 2026 at 15:00 UTC
Product according to CISA: Oracle HTTP Server and Oracle Weblogic Server Proxy Plug-in Filed by this site under “Web and application servers” (indicative classification). Source: KEV catalog, collected September 29, 2026 at 14:57 UTC
CVSS vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:N Technical detail of the score: attack vector, complexity, impact. Source: National Vulnerability Database (NVD), collected September 29, 2026 at 15:00 UTC

Severity and activity

10.0 / 10 CVSS severity: critical

Score from the vendor or CISA, relayed by the NVD. Collected Sep 29, 2026.

— Probability of exploitation in the next 30 days (EPSS)

FIRST’s EPSS model. Since exploitation is already confirmed, this figure is mostly useful to compare activity. Collected Sep 29, 2026.

Description

Vulnerability in the Oracle HTTP Server, Oracle Weblogic Server Proxy Plug-in product of Oracle Fusion Middleware (component: Weblogic Server Proxy Plug-in for Apache HTTP Server, Weblogic Server Proxy Plug-in for IIS). Supported versions that are affected are 12.2.1.4.0, 14.1.1.0.0 and 14.1.2.0.0. Easily exploitable vulnerability allows unauthenticated attacker with network access via HTTP to compromise Oracle HTTP Server, Oracle Weblogic Server Proxy Plug-in. While the vulnerability is in Oracle HTTP Server, Oracle Weblogic Server Proxy Plug-in, attacks may significantly impact additional products (scope change). Successful attacks of this vulnerability can result in unauthorized creation, deletion or modification access to critical data or all Oracle HTTP Server, Oracle Weblogic Server Proxy Plug-in accessible data as well as unauthorized access to critical data or complete access to all Oracle HTTP Server, Oracle Weblogic Server Proxy Plug-in accessible data. Note: Affected version for Weblogic Server Proxy Plug-in for IIS is 12.2.1.4.0 only. CVSS 3.1 Base Score 10.0 (Confidentiality and Integrity impacts). CVSS Vector: (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:N).

Oracle HTTP Server and Oracle Weblogic Server Proxy Plug-in contain an improper access control vulnerability that can result in unauthorized creation, deletion or modification access to critical data as well as unauthorized access to critical data or complete access to all Oracle HTTP Server and Oracle Weblogic Server Proxy Plug-in accessible data.

Summary from CISA (KEV catalog).

CERT-FR advisories

No advisory among the latest CERT-FR publications this site follows. That does not mean there are none.

Information reused under the Open Licence 2.0 (Etalab); the date of last update is shown for each advisory. This site is neither affiliated with nor endorsed by ANSSI.

Sources for this page

CISA KEV catalog: exploitation, date added, required action, deadline, ransomware.
NVD (NIST): CVSS severity, publication date, description, vendor references.
EPSS (FIRST): probability of exploitation.
CERT-FR: advisories and alerts (in French).
Brand and category: indicative classification by this site (method).