Microsoft Windows Storage Link Following Vulnerability
Microsoft · Windows
The Microsoft Windows storage component contains a link-following flaw (CWE-59, improper link resolution before file access), which is the basis of its elevation-of-privilege weakness. An attacker with low-privileged local access can exploit it without user interaction to gain elevated privileges and compromise integrity and availability on the affected system.
Windows Storage Elevation of Privilege Vulnerability
- Exploited
- Yes, in CISA KEV
- Reports
- 0
- Tactics
- 2/15
How an attack unfolds
Based on MITRE ATT&CKA public catalogue of the techniques attackers use, maintained by MITRE. Patchfirst uses it to describe what attackers do with a vulnerability. mappings. Select a step to see the evidence.Exploitation timelineDated milestones for a CVE: when it was disclosed, when exploit code became public, when exploitation was confirmed, and when threat reports named it.
First seen exploited the day it was disclosed.
CISA KEV listing is when exploitation was confirmed, not necessarily the first attack.
MITRE ATT&CKA public catalogue of the techniques attackers use, maintained by MITRE. Patchfirst uses it to describe what attackers do with a vulnerability. techniques
3 TechniqueOne specific attacker behaviour in MITRE ATT&CK, such as T1190 “Exploit Public-Facing Application”. IDs with a dot, like T1059.004, are sub-techniques., grouped by TacticThe attacker’s goal at a stage of an attack in MITRE ATT&CK, such as Initial Access or Persistence. Each technique belongs to one or more tactics. in kill-chain order 3Privilege EscalationTA0004
Exploiting this link-following vulnerability can lead to privilege escalation, with the primary result being deletion of system data. As a consequence of this, deletion of certain files could also make the recovery process more difficult.
ImpactTA0040
Detection
0 rules for this CVE · 78 general rules for its techniquesRules for this CVE
0Sigma ruleAn open, vendor-neutral detection rule for log data. Security teams convert Sigma rules into searches for their own SIEM. that reference CVE-2025-21391 directly.CVE-specific rules are not available in this build. Search SigmaHQ ↗
General rules for this CVE’s techniques
These detect the technique in general, not this specific vulnerability.
Exploitation for Privilege EscalationT106831 general rules
- Exploiting CVE-2019-1388criticalstable
- Audit CVE Eventcriticaltest
- HackTool - SysmonEOP Executioncriticaltest
- InstallerFileTakeOver LPE CVE-2021-41379 File Create Eventcriticaltest
- Possible Coin Miner CPU Priority Paramcriticaltest
- Potential CVE-2021-41379 Exploitation Attemptcriticaltest
- Potential SystemNightmare Exploitation Attemptcriticaltest
- Sudo Privilege Escalation CVE-2019-14287 - Builtincriticaltest
Data DestructionT148520 general rules
- Fsutil Suspicious Invocationhighstable
- Potential BlackByte Ransomware Activityhightest
- Potential File Overwrite Via Sysinternals SDeletehightest
- Renamed Sysinternals Sdelete Executionhightest
- AWS EFS Fileshare Mount Modified or Deletedmediumtest
- Azure Device or Configuration Modified or Deletedmediumtest
- Azure Kubernetes Network Policy Changemediumtest
- Azure Kubernetes RoleBinding/ClusterRoleBinding Modified and Deletedmediumtest
Inhibit System RecoveryT149027 general rules
- Potential Dtrack RAT Activitycriticalstable
- Potential Maze Ransomware Activitycriticaltest
- WannaCry Ransomware Activitycriticaltest
- Boot Configuration Tampering Via Bcdedit.EXEhighstable
- Delete Volume Shadow Copies Via WMI With PowerShellhighstable
- Shadow Copies Deletion Using Operating Systems Utilitieshighstable
- All Backups Deleted Via Wbadmin.EXEhightest
- Copy From VolumeShadowCopy Via Cmd.EXEhightest
Sigma rules © SigmaHQ, Detection Rule License 1.1; linked, not reproduced.
What security researchers reported
Not named in any threat report yetAlso mentioned in 50 community threat pulses (AlienVault OTX)
Weaker evidencePulses are indicator collections that anyone can publish. A mention is not confirmation of exploitation.
- Actively_Exploited_Kev | Oct 30, 202629 Oct 2026
- Actively_Exploited_Kev | Oct 29, 202628 Oct 2026
- Actively_Exploited_Kev | Oct 28, 202627 Oct 2026
- Actively_Exploited_Kev | Oct 27, 202626 Oct 2026
- Actively_Exploited_Kev | Oct 24, 202623 Oct 2026
- Actively_Exploited_Kev | Oct 23, 202622 Oct 2026
- 44 more on OTX