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Threats / Oracle / CVE-2020-14871
CVE-2020-14871 · EUVD no mirror located · GCVE no mirror located Verified 2026-06-22

Oracle Solaris and Zettabyte File System (ZFS) vulnerability

Oracle Solaris and ZFS contain an out-of-bounds write vulnerability affecting confidentiality, integrity, and availability. The flaw is actively exploited in the wild.

Verdict

Today item — known-exploited.

An out-of-bounds write in Oracle Solaris and ZFS enables memory corruption with high impact across confidentiality, integrity, and availability. Active exploitation in the wild indicates immediate risk to deployed systems.

CISA KEV Yes · 2021-11-033EPSS 0.80291 (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
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 2021-11-03).
CISA KEV ↗Confirmed
Probability (EPSS)
EPSS 0.80291 — modeled likelihood of exploitation activity.EPSS is a daily-changing model output — open the source for today's value.
Severity / affected
Affected: Oracle, Solaris and Zettabyte File System (ZFS). Confirm exact fixed builds in the vendor advisory.
NVD ↗Reported
Weakness (CWE)
Mapped to CWE-787 Out-of-bounds Write — weakness family: Memory safety.CWE assignment from the public NVD record; the weakness class drives how the flaw is exploited.
NVD ↗Reported
WeaknessCWE-787 · Out-of-bounds WriteMemory safety
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 input that triggers an out-of-bounds write in the vulnerable code path, corrupting adjacent memory regions.
Business
System memory integrity is compromised, creating conditions for privilege escalation or denial of service.
2

Keys to the kingdom — privilege/identity takeover narrative 2

Attacker
I leverage the memory corruption to escalate privileges or execute arbitrary code with elevated context.
Business
Attackers gain unauthorized access to sensitive data and system controls, violating confidentiality and integrity.
3

Lateral reach — past segmentation narrative 3

Attacker
I maintain persistence or pivot to other systems using the compromised host as a foothold.
Business
Infrastructure availability is degraded; incident response and recovery costs escalate across affected deployments.
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)
  • Weaponized exploit available (VulnCheck)
  • 2 reported-exploitation source(s)
  • CWE weakness mapping (NVD)
  • Public exploit availability
  • Catalogued by oracle (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 oracleCNA
    Credited with finding itNo finder named in the public CVE record — the work behind this find is unattributed.