CVE-2017-9805 KEVPublic exploit High · 8.1 EPSS 99.4%

Apache Struts Deserialization of Untrusted Data Vulnerability

Apache · Struts

Summary

A deserialization flaw in the REST Plugin of Apache Struts 2.1.1 through 2.3.x before 2.3.34 and 2.5.x before 2.5.13 stems from an XStreamHandler that deserializes XML without any type filtering. An attacker who can send crafted XML payloads to an affected REST endpoint can achieve remote code execution, with the attack complexity noted as high and no authentication or user interaction required.

Official description · NVD

The REST Plugin in Apache Struts 2.1.1 through 2.3.x before 2.3.34 and 2.5.x before 2.5.13 uses an XStreamHandler with an instance of XStream for deserialization without any type filtering, which can lead to Remote Code Execution when deserializing XML payloads.

Breakdown

78.7 / 100

Exploited: Yes, in CISA KEV
Reports: 0
Tactics: 2/15

How an attack unfolds

Based on mappings. Select a step to see the evidence.

How attackers get in
- Break in through an internet-facing appT1190 · Exploit Public-Facing ApplicationSource data149 general detection rules
What they do
- Run commands on the systemT1059 · Command and Scripting InterpreterSource data95 general detection rules

First seen exploited 4 years after disclosure. Public exploit code (Metasploit) was available 10 days before disclosure.

Public exploit codeMetasploit5 Sep 201710 days before
Disclosed15 Sep 2017day 0
First seen exploitedVulnCheck KEV evidenceAdded to CISA KEVEU database agrees3 Nov 2021+4 yrs

CISA KEV listing is when exploitation was confirmed, not necessarily the first attack.

6 fixes in struts2-rest-plugin over 4 years. The latest fix listed for struts2-rest-plugin is 2.5.16.

Fixes in struts2-rest-pluginMaven package, by fixed version. Earlier and later fixes in the same package, not necessarily the same bug.

2.3.15.2CVE-2013-431630 Sep 2013
2.3.29CVE-2016-44384 Jul 2016
2.5.13CVE-2017-980515 Sep 2017KEV
2.5.13CVE-2017-979320 Sep 2017
2.5.16CVE-2017-157071 Dec 2017
2.5.16CVE-2018-132727 Mar 2018Latest listed

techniques

2 , grouped by in kill-chain order 2

Initial AccessTA0001

Exploit Public-Facing Application T1190

MITRE CTID mapping of the KEV entry · how it is exploited

CVE-2017-9805 is a deserialization vulnerability in the Apache Struts REST Plugin that could allow an attacker to execute arbitrary commands remotely on the affected systems by sending a specially crafted web request to the application.

ExecutionTA0002

Command and Scripting Interpreter T1059

MITRE CTID mapping of the KEV entry · primary impact

Detection

0 rules for this CVE · 244 general rules for its techniques

Rules for this CVE

0 that reference CVE-2017-9805 directly.

CVE-specific rules are not available in this build. Search SigmaHQ ↗

General rules for this CVE’s techniques

These detect the technique in general, not this specific vulnerability.

Exploit Public-Facing ApplicationT1190149 general rules

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CVE-2010-5278 Exploitation Attemptcriticaltest
CVE-2020-0688 Exchange Exploitation via Web Logcriticaltest
CVE-2020-10148 SolarWinds Orion API Auth Bypasscriticaltest
CVE-2020-5902 F5 BIG-IP Exploitation Attemptcriticaltest

All 149 on SigmaHQ ↗

Command and Scripting InterpreterT105995 general rules

HackTool - Sliver C2 Implant Activity Patterncriticaltest
Lazarus Group Activitycriticaltest
REvil Kaseya Incident Malware Patternscriticaltest
Turla Group Lateral Movementcriticaltest
Windows Defender AMSI Trigger Detectedhighstable
Windows Defender Threat Detectedhighstable
Abusable DLL Potential Sideloading From Suspicious Locationhightest
Add Insecure Download Source To Wingethightest

All 95 on SigmaHQ ↗

Sigma rules © SigmaHQ, Detection Rule License 1.1; linked, not reproduced.

Am I affected? What do I upgrade to?

From GitHub Security Advisories and OSV

1 package in 1 ecosystem. Main package: org.apache.struts:struts2-rest-plugin.

Mavenorg.apache.struts:struts2-rest-pluginGHSA-gg9m-fj3v-r58c

Upgrade to 2.5.13 or later

Set the version to 2.5.13 or later in your pom.xml or build.gradle.

The first fix for CVE-2017-9805. No other CVE tracked by Patchfirst affects this package.

Affected versions, by release line

If you run	Upgrade to
2.5.0 up to 2.5.13	2.5.13
2.1.1 up to 2.3.34	2.3.34

“Up to” means the second version is the fix and is not affected.

Check your lockfile against all CVEs

What security researchers reported

Not named in any threat report yet

Also mentioned in 50 community threat pulses (AlienVault OTX)

Weaker evidence

Pulses are indicator collections that anyone can publish. A mention is not confirmation of exploitation.

Actively_Exploited_Kev | Oct 29, 202628 Oct 2026
Actively_Exploited_Kev | Oct 28, 202627 Oct 2026
Actively_Exploited_Kev | Oct 27, 202626 Oct 2026
Actively_Exploited_Kev | Oct 24, 202623 Oct 2026
Actively_Exploited_Kev | Oct 23, 202622 Oct 2026
Actively_Exploited_Kev | Oct 22, 202621 Oct 2026
44 more on OTX

References

13 links, grouped by NVD tag (12 duplicates merged)

Exploitation evidence

Exploited in the wild

Listed since 3 Nov 2021. Federal due date 3 May 2022. No recorded ransomware use.

Apply updates per vendor instructions.

ENISA

Marked exploited since 3 Nov 2021. EUVD-2018-0602

Apache Struts 2.5 < 2.5.12 - REST Plugin XStream Remote Code ExecutionEDB-42627 · remote · linux · 2017-09-06

, 30 Oct 2026

99.4%Top 0.06%

Chance of exploitation in the next 30 days. of scored CVEs (riskier than 99.94%).

3.1

8.1High · 8.1

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

Priority factorsFormula

In a KEV cataloglisted in CISA KEV and VulnCheck KEV 35.0/35

Recent KEV listingadded 1823 days ago 0.0/10

Known ransomware useCISA KEV and VulnCheck KEV: Known 10.0/10

EPSS percentilepercentile 0.9994 20.0/20

Threat reports0 reports 0.0/10

Public exploit code1 NVD reference tagged Exploit; 1 Exploit-DB entry; 1 advisory exploit reference; 18 PoC-in-GitHub repos; 1 Metasploit module; 1 nuclei template 5.0/5

Mentioned in OTX pulses50 pulses 3.0/3

CVSS base scorebase score 8.1 5.7/7

End-of-life productsupported or unknown 0.0

Total78.7

Record

Published: 15 Sep 2017
Modified: 17 Jun 2026
: CWE-502 Deserialization of Untrusted Data
Elsewhere: NVD CVE.org KEV JSON

How an attack unfolds

1How attackers get in

2What they do

Exploitation timelineExploitation timelineDated milestones for a CVE: when it was disclosed, when exploit code became public, when exploitation was confirmed, and when threat reports named it.

Patch historyPatch historyEarlier and later CVEs in the same code, in date order. It shows when a fix was bypassed or incomplete and which version finally fixed it.

Fixes in struts2-rest-pluginMaven package, by fixed version. Earlier and later fixes in the same package, not necessarily the same bug.

ATT&CKMITRE ATT&CKA public catalogue of the techniques attackers use, maintained by MITRE. Patchfirst uses it to describe what attackers do with a vulnerability. techniques

Initial AccessTA0001

ExecutionTA0002

Detection

Rules for this CVE

General rules for this CVE’s techniques

Am I affected? What do I upgrade to?

Affected versions, by release line

What security researchers reported

Also mentioned in 50 community threat pulses (AlienVault OTX)

References

Vendor Advisory 3

Patch 1

US Government Resource 2

Third Party Advisory 6

Broken Link 1

How attackers get in

What they do

techniques