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Threats / Microsoft / CVE-2015-0016
CVE-2015-0016 · EUVD no mirror located · GCVE no mirror located Verified 2026-06-22

Microsoft Windows vulnerability

Directory traversal vulnerability in Microsoft Windows TS WebProxy component allows remote attackers to escalate privileges.

Verdict

Today item — known-exploited.

A path traversal flaw in the Terminal Services WebProxy enables unauthenticated remote privilege escalation. Active exploitation in the wild with high EPSS score indicates immediate risk to exposed systems.

CISA KEV Yes · 2022-05-253EPSS 0.7594 (verify live)4
01

Is it exploitable?

— the evidence, ranked above the score
Reported exploitation
2 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 2022-05-25).
CISA KEV ↗Confirmed
Probability (EPSS)
EPSS 0.7594 — modeled likelihood of exploitation activity.EPSS is a daily-changing model output — open the source for today's value.
Severity / affected
Affected: Microsoft, Windows. Confirm exact fixed builds in the vendor advisory.
NVD ↗Reported
Weakness (CWE)
Mapped to CWE-22 Path Traversal — weakness family: Path traversal / file.CWE assignment from the public NVD record; the weakness class drives how the flaw is exploited.
NVD ↗Reported
WeaknessCWE-22 · Path TraversalPath 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 a malicious request with directory traversal sequences to bypass access controls in TS WebProxy.
Business
Attacker gains unauthorized file system access on the Windows host running Terminal Services.
2

Keys to the kingdom — privilege/identity takeover narrative 2

Attacker
I leverage the traversal to read or modify sensitive system files or configuration data.
Business
System integrity is compromised, enabling further lateral movement and persistence.
3

Lateral reach — past segmentation narrative 3

Attacker
I escalate my privileges from the WebProxy context to system or administrator level.
Business
Attacker achieves full control of the affected Windows system and can access all organizational data and resources.
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)
  • EPSS probability (FIRST)
  • 2 reported-exploitation source(s)
  • CWE weakness mapping (NVD)
  • Catalogued by microsoft (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 microsoftCNA
    Credited with finding itNo finder named in the public CVE record — the work behind this find is unattributed.