What is CVE-2012-0391?

CVE-2012-0391 is a critical-severity vulnerability in Apache Struts, classified under Code Injection. CVSS score: 9.8/10. Published 2012-01-08.

How severe is CVE-2012-0391?

Critical severity. CVSS v3 base score is 9.8 out of 10.

Is CVE-2012-0391 known to be exploited?

Yes. CVE-2012-0391 is listed in the CISA Known Exploited Vulnerabilities catalog (added 2022-01-21), indicating it is being actively exploited. 7 public proof-of-concept repositories are indexed.

RCE in Apache Struts

CVE-2012-0391

The ExceptionDelegator component in Apache Struts before 2.2.3.1 interprets parameter values as OGNL expressions during certain exception handling for mismatched data types of properties, which allows remote attackers to execute arbitrary Java code via a crafted parameter.

Vulnerability class: RCE (Remote Code Execution)

Published 2012-01-08 · last modified 2026-06-16.

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.756 (99.5th percentile), scored 2026-10-17.

High probability of exploitation in the next 30 days — patch promptly. 100th percentile — 99.5% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.756 · newest: 0.756 · change: 0.000

Affected products

Apache Struts

Weakness classification (CWE)

CWE-94 — Code Injection

CISA KEV (Known Exploited Vulnerabilities)

This CVE is on the CISA KEV catalog, added on 2022-01-21. CISA KEV inclusion means CISA has confirmed in-the-wild exploitation; US federal agencies are required to remediate within a published due date.

BOD 22-01 due date: 2022-07-21.

Required action: Apply updates per vendor instructions.

Public proof-of-concept exploits

References

www.exploit-db.com/exploits/18329 (Exploit, exploit)
archives.neohapsis.com/archives/bugtraq/2012-01/0031.html (mailing-list, Exploit, Broken Link)
struts.apache.org/2.x/docs/version-notes-2311.html (Vendor Advisory)
struts.apache.org/2.x/docs/s2-008.html (Vendor Advisory)
www.sec-consult.com/files/20120104-0_Apache_Struts2_Multiple_Critical_Vulnerabi… (Exploit, Broken Link)
issues.apache.org/jira/browse/WW-3668 (Vendor Advisory)
secunia.com/advisories/47393 (Vendor Advisory, third-party-advisory)
134c704f-9b21-4f2e-91b3-4a467353bcc0 (US Government Resource)

Frequently asked questions

What is CVE-2012-0391?: CVE-2012-0391 is a critical-severity vulnerability in Apache Struts, classified under Code Injection. CVSS score: 9.8/10. Published 2012-01-08.
How severe is CVE-2012-0391?: Critical severity. CVSS v3 base score is 9.8 out of 10.
Is CVE-2012-0391 known to be exploited?: Yes. CVE-2012-0391 is listed in the CISA Known Exploited Vulnerabilities catalog (added 2022-01-21), indicating it is being actively exploited. 7 public proof-of-concept repositories are indexed.