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Threats / Apache / CVE-2017-12615
CVE-2017-12615 · EUVD no mirror located · GCVE no mirror located Verified 2026-06-22

Apache Tomcat vulnerability

Apache Tomcat on Windows with HTTP PUTs enabled allows remote code execution through JSP file upload via specially crafted requests.

Verdict

Today item, not a backlog item.

An unauthenticated attacker can upload malicious JSP files to a vulnerable Tomcat server and execute arbitrary code with server privileges. This vulnerability has been actively exploited in ransomware campaigns.

CISA KEV Yes · 2022-03-253Ransomware use Flagged3EPSS 0.99607 (verify live)4Exploit Weaponized · public PoC5
01

Is it exploitable?

— the evidence, ranked above the score
Exploit 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
171 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 2022-03-25), flagged for known ransomware use.
CISA KEV ↗Confirmed
Probability (EPSS)
EPSS 0.99607 — modeled likelihood of exploitation activity.EPSS is a daily-changing model output — open the source for today's value.
Severity / affected
Affected: Apache, Tomcat. Confirm exact fixed builds in the vendor advisory.
NVD ↗Reported
Weakness (CWE)
Mapped to CWE-434 Unrestricted File Upload — weakness family: Path traversal / file.CWE assignment from the public NVD record; the weakness class drives how the flaw is exploited.
NVD ↗Reported
WeaknessCWE-434 · Unrestricted File UploadPath traversal / file
02

Who’s exploiting it?

— attribution turns risk into urgency
Attribution not established

No confirmed (advisory-backed) threat-actor attribution is established 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 board
1

Front door — unauthenticated access narrative 1

Attacker
I craft an HTTP PUT request targeting a JSP file path on the Tomcat server.
Business
The organization's web server becomes a direct attack vector for code execution.
2

Keys to the kingdom — privilege/identity takeover narrative 2

Attacker
I upload a malicious JSP file that executes when accessed by any subsequent HTTP request.
Business
Attackers gain persistent remote code execution capability within the application environment.
3

Lateral reach — past segmentation narrative 3

Attacker
I request the uploaded JSP to trigger execution of embedded malicious code on the server.
Business
Ransomware or other payloads deploy across systems, leading to data encryption, exfiltration, or operational disruption.
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’t

Established (cited)

  • KEV listing (CISA)
  • Ransomware-use flag (CISA)
  • EPSS probability (FIRST)
  • Weaponized exploit available (VulnCheck)
  • 171 reported-exploitation source(s)
  • CWE weakness mapping (NVD)
  • Public exploit availability
  • Catalogued by apache (CNA)
  • Coverage gaps — stated, not hidden

  • No EUVD / GCVE mirror in feed — single-authority dependency for the identifier.
  • EPSS & exposure are time-varying; verify live at the source.
  • Threat-actor attribution not established from feed data — absence of a name is not absence of compromise.
  • No finder/reporter credit recorded in the public CVE entry — the work behind this find is unattributed.
  • Disclosure & credit2
    Catalogued by apacheCNA
    Credited with finding itNo finder named in the public CVE record — the work behind this find is unattributed.