How severe is CVE-2012-0391?

CVE-2012-0391 has a CVSS score of 9.8/10, rated CRITICAL. Immediate patching is strongly recommended.

Which packages are affected by CVE-2012-0391?

Affected package information for CVE-2012-0391 is not yet fully mapped. Check the official advisory links for details.

How do I fix CVE-2012-0391?

No fixed version has been published for CVE-2012-0391 yet. Monitor the advisory for updates, apply mitigations recommended by the vendor, and use O3 Security to track when a fix becomes available in your stack.

Is CVE-2012-0391 actively exploited in the wild?

Yes. There are 7 known exploit references for CVE-2012-0391, including 2 documented proof-of-concept exploits on Exploit-DB and 5 in-the-wild exploitations observed on GitHub and other sources. Treat this as actively exploitable and prioritize patching immediately. All exploit code should only be run in an isolated sandbox environment for research or authorized testing — never against production systems without explicit written authorization.

What is the EPSS score for CVE-2012-0391?

CVE-2012-0391 has an EPSS (Exploit Prediction Scoring System) score of 87.5%, placing it in the 99th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. A score above 50% indicates significantly elevated exploitation risk — immediate patching is strongly recommended.

Is CVE-2012-0391 in the CISA Known Exploited Vulnerabilities catalog?

Yes. CVE-2012-0391 (Apache Struts 2 Improper Input Validation Vulnerability) was added to CISA's Known Exploited Vulnerabilities (KEV) catalog on 2022-01-21. CISA required all US federal civilian agencies to remediate this vulnerability by 2022-07-21. The required action was: Apply updates per vendor instructions. Being listed in the KEV catalog is the strongest possible confirmation of active exploitation — treat this as a critical priority.

What type of vulnerability is CVE-2012-0391?

CVE-2012-0391 is classified as Code Injection (CWE-94). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation. This is a high-impact weakness class that often enables remote code execution or data exposure.

Which products and versions are affected by CVE-2012-0391?

CVE-2012-0391 affects apache struts. Check the affected-products list on this page against your deployed version to confirm exposure.

When was CVE-2012-0391 published, and has it been updated?

CVE-2012-0391 was published on January 8, 2012 and was last updated on April 22, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

CISA KEV·Added 2022-01-21 — agencies required to remediate by 2022-07-21

CVE-2012-0391

CRITICAL

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,…

Published

Jan 8, 2012

Updated

Apr 22, 2026

Affected

0 pkgs

Patched

None yet

Exploits

7 known

EPSS Exploitation Probability

via FIRST.org ↗

87.5%probability of exploitation in next 30 days

Very High Risk99th percentile0.00%

EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.

Description

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.

Affected Products

1 product · 1 configurations

Application

strutsapache

< 2.2.3.1

range

Exploits & PoCs

Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.

EDB-18329webappsmultiple✓ Verified

Apache Struts 2 < 2.3.1 - Multiple Vulnerabilities

by SEC Consult · Jan 6, 2012

Exploit-DB Source

EDB-18984remotemultiple✓ Verified

Apache Struts 2.2.1.1 - Remote Command Execution (Metasploit)

by Metasploit · Jun 5, 2012

Exploit-DB Source

Frequently Asked Questions

O3 Security · Impact-Aware SCA

Is CVE-2012-0391 in your stack?

O3 detects CVE-2012-0391 across dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.

Scan my stack How O3 SCA works

CVSS Score

9.8/10

CVSS v3 base score

Vector breakdown

AV:Attack Vector

Network

AC:Attack Complexity

Low

PR:Privileges Required

None

UI:User Interaction

None

S:Scope

Unchanged

C:Confidentiality

High

I:Integrity

High

A:Availability

High

Raw vector

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

CWE Classification

CWE-94Code Injection

Weaponization

No known public exploit tooling found.

Timeline

First exploit

Jan 6, 2012

Disclosed

Jan 8, 2012

KEV added

Jan 21, 2022

Last updated

Apr 22, 2026

Identifiers

CVE-2012-0391

References

Advisorysecunia.com Advisorystruts.apache.org Advisorystruts.apache.org Advisoryissues.apache.org Advisorysecunia.com Advisorystruts.apache.org Advisorystruts.apache.org Advisoryissues.apache.org Exploit / PoCarchives.neohapsis.com Exploit / PoCexploit-db.com Exploit / PoCsec-consult.com Exploit / PoCarchives.neohapsis.com Exploit / PoCexploit-db.com Exploit / PoCsec-consult.com Webcisa.gov

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