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Threats / Red Hat / CVE-2021-3560
CVE-2021-3560 · EUVD no mirror located · GCVE no mirror located Verified 2026-06-22

Red Hat Polkit vulnerability

Red Hat Polkit contains an authorization bypass vulnerability in D-Bus credential checking that allows privilege escalation.

Verdict

Today item — known-exploited.

An unauthenticated local attacker can bypass Polkit's credential validation on D-Bus requests to gain elevated privileges. The vulnerability has been exploited in the wild but is not associated with ransomware campaigns.

CISA KEV Yes · 2023-05-123EPSS 0.22193 (verify live)4Exploit Public PoC5
01

Is it exploitable?

— the evidence, ranked above the score
Exploit available
Public proof-of-concept exploit code is cataloged for this vulnerability.We link the existence of the exploit; we do not host or redistribute payloads.
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 2023-05-12).
CISA KEV ↗Confirmed
Probability (EPSS)
EPSS 0.22193 — modeled likelihood of exploitation activity.EPSS is a daily-changing model output — open the source for today's value.
Severity / affected
Affected: Red Hat, Polkit. Confirm exact fixed builds in the vendor advisory.
NVD ↗Reported
Weakness (CWE)
Mapped to CWE-863 Incorrect Authorization — weakness family: Authorization / access control.CWE assignment from the public NVD record; the weakness class drives how the flaw is exploited.
NVD ↗Reported
WeaknessCWE-863 · Incorrect AuthorizationAuthorization / access control
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 D-Bus request that exploits the credential check bypass in Polkit.
Business
An unprivileged user gains unauthorized administrative access to the system.
2

Keys to the kingdom — privilege/identity takeover narrative 2

Attacker
I use elevated privileges to modify system configuration, install malware, or access sensitive data.
Business
System integrity is compromised, exposing the organization to data theft, service disruption, and compliance violations.
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)
  • Public PoC available (VulnCheck)
  • 1 reported-exploitation source(s)
  • CWE weakness mapping (NVD)
  • Public exploit availability
  • Catalogued by redhat (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 redhatCNA
    Credited with finding itNo finder named in the public CVE record — the work behind this find is unattributed.