CVE-2022-24521
Exploitation: active CVSS 7.8 HIGH Ransomware: known useCVSS base score: 7.8 (High) vendor CNA · v3.1
Score assigned by the vendor's own CVE Numbering Authority (CNA); CISA's Vulnrichment program adds a score only when the CNA omits one. Vulnrichment source record → (opens in a new tab)
Microsoft Windows CLFS Driver Privilege Escalation Vulnerability
Vendor: Microsoft Product: Windows
Description
Microsoft Windows Common Log File System (CLFS) Driver contains an unspecified vulnerability that allows for privilege escalation.
Research & News Coverage
No mentions found in monitored research blogs or news feeds.
Lifecycle Timeline
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2022-04-12Vendor fix publishedMicrosoft shipped a fix for Windows Common Log File System Driver.
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2022-04-13Added to CISA KEV 1 day laterListed as known exploited, which starts the federal remediation clock.
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2022-04-15
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2022-05-04Federal remediation due 19 days laterDeadline for federal civilian agencies under BOD 22-01 (since revoked and replaced by BOD 26-04) — now passed.Exposure depends on the asset KEV yes Automatable no Technical impact total control Window 3 days + forensic triage if exposedCISA KEV
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2026-02-19Public exploit code 3.8 years laterPublic GitHub repository uname1able/CVE-2022-24521 — unvetted, may contain malware
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not recordedEPSS flags exploitation riskTracked, and has never reached 10% (peak 8.7%).
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not recordedFirst national advisoryNo tracked government advisory analyses this CVE. Routine KEV catalog-addition alerts do not count here.
Each milestone comes from a different source, so gaps between them are gaps in what those sources publish, not evidence that nothing happened. EPSS history for this CVE holds 293 points from 2022-04-16, tracked daily from 2026-09-09; earlier points are weekly, which dates a spike to within a week. Peak probability 8.7% on 2026-02-07.
Published Applicability
Check whether a specific version is affected →
What each source publishes about which product versions carry this vulnerability, kept as written rather than merged. Absence here means no source has published applicability data, not that nothing is affected.
Detection & Exploitation
Coverage across public collections only: Nuclei and OpenVAS NVT (scan);
Snort and Suricata ET Open (network); Sigma and YARA (host/SIEM);
Metasploit, Exploit-DB, public GitHub repositories and NVD exploit references (exploit). Absence
here means nothing public was found, not that detection is impossible.
GitHub PoC repositories are collected automatically by
PoC-in-GitHub (opens in a new tab) (CC0) and filtered to repositories that are
still online, contain code, and are starred or at least two weeks old. They are
still not vetted: some are fakes and some are malware. Treat
them as evidence that code was published, not as code to run.
NVD exploit references are links NVD's analysts tag as exploits; they confirm
an exploit was referenced but carry no date. This product uses data from the
NVD but is not endorsed or certified by the NVD.
OpenVAS coverage derives from the Greenbone Community Feed, made available
under the Open Database License (ODbL) v1.0 (opens in a new tab);
its individual Vulnerability Tests are licensed
GNU GPL v2 (opens in a new tab).
| First seen | Tool | Evidence | Earliest reference |
|---|---|---|---|
| 2026-02-19 | GitHub PoC | Unvetted — public repository | uname1able/CVE-2022-24521 (opens in a new tab) |
Metasploit is dated by the first commit of the module file, Exploit-DB by its publication date, and GitHub repositories by their creation date. GitHub PoC repositories are filtered (still online, contain code, starred or at least two weeks old) but not vetted: some are fakes and some are malware, so they show that code was published, not that it works or is safe to run. Evidence tiers are explained on the About page.
Microsoft Assessment
published by the affected vendor via MSRCWindows Common Log File System Driver Elevation of Privilege Vulnerability
The vendor's own judgement about their own code, shown alongside CISA's rather than merged into it. The exploitability index is a forward-looking prediction, distinct from a CVSS severity or CISA's SSVC decision, and vendors often report observed exploitation before a CVE reaches the KEV catalog. Vendor advisory → (opens in a new tab)
CISA Assessment (Vulnrichment / SSVC)
Federal Remediation Window (BOD 26-04)
| If the asset is | Remediate within | Table 1 row |
|---|---|---|
| Publicly exposed | 3 days + forensic triage | 3 of 16 |
| Not publicly exposed | 14 days | 11 of 16 |
BOD 26-04 (opens in a new tab) replaced the single KEV deadline of BOD 22-01 with four inputs: whether the asset is publicly exposed, KEV status, whether exploitation is automatable, and technical impact. Exposure belongs to each agency's asset, not to the CVE, so both outcomes are shown. Automatable and technical impact come from the CISA assessment above. Days are calendar days; for KEV entries the clock starts on the date it was added. Agencies make the final exposure call asset by asset, and may set shorter timelines.
D3FEND Countermeasures
Defensive techniques inferred by MITRE D3FEND (opens in a new tab) from the underlying weakness (CWE-787) — general hardening and detection guidance for this weakness class, not a vendor patch for this specific CVE.