CVE-2018-11776

Apache Struts: Remote Code Execution

As of , CVE-2018-11776 in Apache Struts is on CISA's list of exploited vulnerabilities: CISA listed it on . Our patch-first group: Patch this week.

Exploited
Yes: CISA listed it on 3 November 2021
US federal deadline
3 May 2022181 days after CISA listed it. US federal civilian agencies must fix it by then.
Used in ransomware campaigns
Not known to CISA
EPSS score
0.99Higher than 99% of the CVEs EPSS scores. EPSS estimates the chance of exploitation activity in the next 30 days.
EPSS when listed
Not availableCISA listed it before 4 February 2022, where the EPSS files we read begin.
Public exploit
1 Metasploit module and 3 Exploit-DB entries (1 verified)
Fix
No vendor link in CISA's entry

What CISA says to do

Apply updates per vendor instructions.

CISA's required action

What the flaw is

Apache Struts contains a vulnerability that allows for remote code execution under two circumstances. One, where the alwaysSelectFullNamespace option is true and the value isn't set for a result defined in underlying configurations and in same time, its upper package configuration have no or wildcard namespace. Or, using URL tag which doesn't have value and action set and in same time, its upper package configuration have no or wildcard namespace.

CISA's description

Apache Struts versions 2.3 to 2.3.34 and 2.5 to 2.5.16 suffer from possible Remote Code Execution when alwaysSelectFullNamespace is true (either by user or a plugin like Convention Plugin) and then: results are used with no namespace and in same time, its upper package have no or wildcard namespace and similar to results, same possibility when using url tag which doesn't have value and action set and in same time, its upper package have no or wildcard namespace.

The CVE record's description, from apache

CVE published
22 August 2018
Assigned by
apache
CVSS
8.1 High (CVSS 3.1, from CISA-ADP)
CWE-20
Improper Input Validation
CISA SSVC, exploitation
active
CISA SSVC, automatable
no
CISA SSVC, technical impact
total

Timeline

  1. The CVE record was published.
  2. Exploit-DB published an exploit (EDB-ID 45262).
  3. Exploit-DB published an exploit (EDB-ID 45260).
  4. Exploit-DB published an exploit (EDB-ID 45367).
  5. CISA added it to its list of exploited vulnerabilities.
  6. 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-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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