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Threats / Ivanti / CVE-2021-22900
CVE-2021-22900 · EUVD no mirror located · GCVE no mirror located Verified 2026-06-22

Ivanti Pulse Connect Secure vulnerability

Ivanti Pulse Connect Secure contains an unrestricted file upload vulnerability allowing authenticated administrators to write arbitrary files via malicious archive uploads in the web interface.

Verdict

Today item — known-exploited.

An authenticated administrator can exploit improper input validation on archive uploads to write files to the system, potentially enabling code execution or system compromise through CWE-94 code injection mechanisms.

CISA KEV Yes · 2021-11-033EPSS 0.14146 (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 2021-11-03).
CISA KEV ↗Confirmed
Probability (EPSS)
EPSS 0.14146 — modeled likelihood of exploitation activity.EPSS is a daily-changing model output — open the source for today's value.
Severity / affected
Affected: Ivanti, Pulse Connect Secure. Confirm exact fixed builds in the vendor advisory.
NVD ↗Reported
Weakness (CWE)
Mapped to CWE-94 Code Injection — weakness family: Injection.CWE assignment from the public NVD record; the weakness class drives how the flaw is exploited.
NVD ↗Reported
WeaknessCWE-94 · Code InjectionInjection
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 archive file designed to bypass upload validation controls.
Business
Administrative access controls fail to prevent unauthorized file placement on critical infrastructure.
2

Keys to the kingdom — privilege/identity takeover narrative 2

Attacker
I upload the archive through the administrator web interface, exploiting the lack of proper file type or content restrictions.
Business
The system processes untrusted input without adequate sanitization, creating an execution pathway.
3

Lateral reach — past segmentation narrative 3

Attacker
I write arbitrary files to sensitive directories on the Pulse Connect Secure server.
Business
System integrity is compromised as attacker-controlled files are placed in executable or configuration locations.
4

Data at risk — exfiltration narrative 4

Attacker
I trigger code execution by accessing the written files or leveraging them in subsequent operations.
Business
The VPN appliance is fully compromised, enabling lateral movement into protected networks and data exfiltration.
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 hackerone (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 hackeroneCNA
    Credited with finding itNo finder named in the public CVE record — the work behind this find is unattributed.