high Known exploitedREV. 01

CVE-2026-21533Windows Remote Desktop — improper privilege management

Windows Remote Desktop Services manages privileges improperly, so a user who already holds an account on the machine can raise themselves beyond what that account was ever meant to allow.

YOUR NEXT MOVE

Install the Microsoft update for this CVE now; session hosts carry many users at once, so patch those ahead of single-user desktops.

Read the risk

THE VITAL STATS
CVSS score
7.8/ 10
CVSS v3.1
EPSS probability
4%
Likelihood of exploitation
Attack complexity
Low
Conditions needed to exploit
Known exploited
Yes — CISA KEV
CVE published
2026-02-10
Added to KEV
2026-02-10
Exploit published
Not recorded
Confidence
high
Kill chain
privilege escalation
MITRE ATT&CK
T1068
Severity
high

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Attacker needsAn existing account on the machine, signed in locally or over a remote session.

Behind the card

5 REFERENCES
Field-level provenanceTRACE THE SOURCES +

Which source supports each field, when it was retrieved, and who extracted it.

FieldsSourceRetrievedExtractorConfidence
cvss, exploitation.attack_complexity, exploitation.exploit_available, references, published_atnvd.nist.gov2026-09-24scrty-crds-pipeline/0.1high
exploitation.known_exploited, exploitation.kev_addedcisa.gov2026-09-24scrty-crds-pipeline/0.1high
epssapi.first.org2026-09-24scrty-crds-pipeline/0.1high
title, summary, severity, remediation, mitre_attack, kill_chain, recommended_action, confidence, tags, exploitation.prerequisitesnvd.nist.gov2026-09-24claude-codehigh

Printing history

THE RECORD
  1. r1Initial base card

First printing. This card has not been reprinted since publication.

crds:cve-2026-21533 · CRDS 0.1 · Issued 2026-09-24