Threats / Apache / CVE-2017-5638
CVE-2017-5638
· EUVD no mirror located
· GCVE no mirror located
Verified 2026-06-16
Apache Struts vulnerability
Apache Struts Jakarta Multipart parser vulnerability allows remote code execution through malicious Content-Type values in file uploads.
Verdict
Today item, not a backlog item.
A critical input validation flaw in Apache Struts enables unauthenticated remote code execution via crafted multipart requests. The vulnerability has been actively exploited in ransomware campaigns and carries high real-world risk.
CISA KEV Yes · 2021-11-033Ransomware use Flagged3EPSS 0.99999 (verify live)4Exploit Weaponized · public PoC5
01
Is it exploitable?
— the evidence, ranked above the scoreExploit available
Fully weaponized — public exploit code is cataloged for this vulnerability.We link the existence of the exploit; we do not host or redistribute payloads.
Reported exploitation
513 independent public reports of in-the-wild exploitation are cataloged.Distinct reporting sources (vendor, incident response, government); open them for the underlying claims.
Exploited in the wild
Listed in the CISA Known Exploited Vulnerabilities catalog (added 2021-11-03), flagged for known ransomware use.
Probability (EPSS)
EPSS 0.99999 — modeled likelihood of exploitation activity.EPSS is a daily-changing model output — open the source for today's value.
Severity / affected
Affected: Apache, Struts. Confirm exact fixed builds in the vendor advisory.
Weakness (CWE)
Mapped to CWE-20 Improper Input Validation.CWE assignment from the public NVD record; the weakness class drives how the flaw is exploited.
02
Who’s exploiting it?
— attribution turns risk into urgencyAttribution not established
No threat-actor attribution is established from the public feed for this record. Absence of a named actor is not absence of compromise — see Coverage & confidence.
03
Why it matters
— the attack path, told twice: adversary, then board1
Front door — unauthenticated access narrative 1
Attacker
I craft a malicious HTTP request with a specially formatted Content-Type header in a multipart form submission.
Business
The organization faces immediate risk of complete system compromise and data exfiltration.
2
Keys to the kingdom — privilege/identity takeover narrative 2
Attacker
I bypass input validation in the Jakarta Multipart parser to inject arbitrary code that executes on the server.
Business
Attackers gain unrestricted command execution within the application's security context.
3
Lateral reach — past segmentation narrative 3
Attacker
I establish persistent access and deploy ransomware or data theft tools across the infrastructure.
Business
The organization suffers operational shutdown, financial extortion demands, and regulatory breach notification obligations.
04
What to do
— defensible action- Remediate per the vendor advisory — confirm the fixed build for your version and verify exposure.1
Say it to the boardA vulnerability with this evidence profile is a defensible budget line, not a backlog ticket — fund the change against the proof above.
05
Coverage & confidence
— what we know, and what we don’tEstablished (cited)
Coverage gaps — stated, not hidden
Disclosure & credit2
Catalogued by apacheCNA
Credited with finding itNo finder named in the public CVE record — the work behind this find is unattributed.