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Threats / Zoho / CVE-2021-37415
CVE-2021-37415 · EUVD no mirror located · GCVE no mirror located Verified 2026-06-22

Zoho ManageEngine ServiceDesk Plus (SDP) vulnerability

Zoho ManageEngine ServiceDesk Plus before version 11302 contains an authentication bypass vulnerability affecting certain REST API endpoints, allowing unauthenticated access.

Verdict

Today item — known-exploited.

An attacker can bypass authentication controls to access sensitive REST API functionality in ServiceDesk Plus without valid credentials. This vulnerability is actively exploited in the wild and enables unauthorized system interaction.

CISA KEV Yes · 2021-12-013EPSS 0.99579 (verify live)4
01

Is it exploitable?

— the evidence, ranked above the score
Reported exploitation
1 independent public report of in-the-wild exploitation are cataloged.Distinct reporting sources (vendor, incident response, government); open them for the underlying claims.
cisa.gov ↗Confirmed
Exploited in the wild
Listed in the CISA Known Exploited Vulnerabilities catalog (added 2021-12-01).
CISA KEV ↗Confirmed
Probability (EPSS)
EPSS 0.99579 — modeled likelihood of exploitation activity.EPSS is a daily-changing model output — open the source for today's value.
Severity / affected
Affected: Zoho, ManageEngine ServiceDesk Plus (SDP). Confirm exact fixed builds in the vendor advisory.
NVD ↗Reported
Weakness (CWE)
Mapped to CWE-306 Missing Authentication — weakness family: Authentication.CWE assignment from the public NVD record; the weakness class drives how the flaw is exploited.
NVD ↗Reported
WeaknessCWE-306 · Missing AuthenticationAuthentication
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 identify unauthenticated REST API endpoints exposed by the application.
Business
Attackers gain direct access to critical service desk functions without credential validation.
2

Keys to the kingdom — privilege/identity takeover narrative 2

Attacker
I invoke protected API operations to retrieve or manipulate service desk data.
Business
Confidential ticket information, user data, and system configurations become accessible to unauthorized parties.
3

Lateral reach — past segmentation narrative 3

Attacker
I escalate access by leveraging API functions to modify system settings or create administrative accounts.
Business
Complete compromise of the service desk platform enables lateral movement into dependent business systems.
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)
  • 1 reported-exploitation source(s)
  • CWE weakness mapping (NVD)
  • Catalogued by mitre (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 mitreCNA
    Credited with finding itNo finder named in the public CVE record — the work behind this find is unattributed.