CVE-2021-36934
What it is
An elevation of privilege vulnerability exists because of overly permissive Access Control Lists (ACLs) on multiple system files, including the Security Accounts Manager (SAM) database. An attacker who successfully exploited this vulnerability could run arbitrary code with SYSTEM privileges. An attacker could then install programs; view, change, or delete data; or create new accounts with full user rights. An attacker must have the ability to execute code on a victim system to exploit this vulnerability. After installing this security update, you must manually delete all shadow copies of system files, including the SAM database, to fully mitigate this vulnerabilty. Simply installing this security update will not fully mitigate this vulnerability. See KB5005357- Delete Volume Shadow Copies.
At a glance
- Exploitability
- Can be exploited locally on the machine with a low-privilege account. High risk of data exposure, data tampering, service disruption.
- In the wild
- CISA lists this as exploited in real attacks. Treat as urgent.
- Fix
- A patch, advisory or fixed version is referenced. Upgrade or apply it.
Timeline
- ReservedThe CVE id was reserved by its CNA
- PublishedDisclosed publicly on CVE.org and NVD
- 2022-02-10 Exploited in the wildAdded to CISA's Known Exploited Vulnerabilities list
- 2022-02-24 Remediation deadlineCISA's due date for federal agencies to fix it
- Last updatedMost recent change to the record
Why it ranks here
- Exploited in the wild: yes, CISA lists it. This puts it above everything that is not.
- Exploit odds: 67.3% in the next 30 days (EPSS).
- Severity: 7.8 HIGH (CVSS).
- Fix: a patch or advisory is linked.
Details
- Published
- Last modified
- Added to CISA KEV
- 2022-02-10
- Exploit probability
- 67.3% · EPSS, next 30 days
- Record status
- Analyzed
Affected
- Microsoft Windows 10 1809 < 10.0.17763.2114
- Microsoft Windows 10 1909 < 10.0.18363.1734
- Microsoft Windows 10 2004 < 10.0.19041.1165
- Microsoft Windows 10 20h2 < 10.0.19042.1165
- Microsoft Windows 10 21h1 < 10.0.19043.1165
Attack profile CVSS 3.1 · 7.8
- Attack vector
- Local
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Raw vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Is it in your code?
Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.
Read https://cve-list.com/agent/cve/CVE-2021-36934.md and follow it. Check whether this project is affected by CVE-2021-36934. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.
Fix and advisories
- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-36934
- https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-36934
References
- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-36934
- http://packetstormsecurity.com/files/164006/HiveNightmare-AKA-SeriousSAM.html
- https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-36934
- https://www.kb.cert.org/vuls/id/506989
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-36934