CVE-2016-3081

Apache Struts: Command Injection

As of , CVE-2016-3081 in Apache Struts is on CISA's list of exploited vulnerabilities: CISA listed it on . Our patch-first group: Patch now.

Exploited
Yes: CISA listed it on 8 October 2026
US federal deadline
11 October 20263 days after CISA listed it. US federal civilian agencies must fix it by then.
Used in ransomware campaigns
Not known to CISA
Forensic triage
Required by CISA under BOD 26-04Agencies must also look for signs that attackers already got in.
EPSS score
0.96Higher than 99% of the CVEs EPSS scores. EPSS estimates the chance of exploitation activity in the next 30 days.
EPSS when listed
0.93 on 8 October 2026EPSS on the day CISA listed it.
Public exploit
1 Metasploit module and 1 Exploit-DB entry (1 verified)
Fix
Vendor advice: cwiki.apache.orgLinks below, from CISA's entry.

What CISA says to do

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.

CISA's required action

  • cwiki.apache.orgThis vulnerability could affect an open-source component, third-party library, protocol, or proprietary implementation that could be used…

What the flaw is

Apache Struts contains a command injection vulnerability that could allow remote attackers to execute arbitrary code via method:prefix when Dynamic Method Invocation is enabled.

CISA's description

Apache Struts 2.3.19 to 2.3.20.2, 2.3.21 to 2.3.24.1, and 2.3.25 to 2.3.28, when Dynamic Method Invocation is enabled, allow remote attackers to execute arbitrary code via method: prefix, related to chained expressions.

The CVE record's description, from redhat

CVE published
26 April 2016
Assigned by
redhat
CVSS
8.1 High (CVSS 3.1, from CISA-ADP)
CWE-77
Improper Neutralization of Special Elements used in a Command ('Command Injection')
CISA SSVC, exploitation
active
CISA SSVC, automatable
no
CISA SSVC, technical impact
total

EPSS since listing

0.250.500.750.50: the rank's Patch this week lineListed by CISA0.93 on 8 October 20260.96 since 10 October 2026
EPSS for CVE-2016-3081 since CISA listed it, on the days its value to 2 decimals changed. EPSS scores by FIRST.
Show the numbers
FromEPSS
0.93
0.95
0.96

Timeline

  1. The CVE record was published.
  2. Exploit-DB published an exploit (EDB-ID 39756).
  3. CISA added it to its list of exploited vulnerabilities.
  4. The US federal deadline to fix it.

Public exploits

Facts from Metasploit's module list and Exploit-DB's index; we never copy exploit code.

Struts: other exploited entries

VulnerabilityProductOur groupListedDeadlineEPSS
CVE-2013-2251Improper Input ValidationApache StrutsPatch this weekMetasploit module; EPSS 0.99; verified Exploit-DB entry0.99
CVE-2017-5638Remote Code ExecutionApache StrutsPatch this weekRansomware use; Metasploit module; EPSS 0.99; verified Exploit-DB entry0.99
CVE-2018-11776Remote Code ExecutionApache StrutsPatch this weekMetasploit module; EPSS 0.99; verified Exploit-DB entry0.99
CVE-2017-9805Deserialization of Untrusted DataApache StrutsPatch this weekMetasploit module; EPSS 0.990.99
CVE-2020-17530Remote Code ExecutionApache StrutsPatch this weekMetasploit module; EPSS 0.960.96

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