Microsoft Windows Search Remote Code Execution
CVE-2017-8543 is a critical-severity improper preservation of permissions vulnerability in Microsoft Windows from Microsoft, with a CVSS 3.1 base score of 9.8 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. CISA added it to the Known Exploited Vulnerabilities catalogue on May 24, 2022, which means attacks have been observed in the wild.
Attackers are already exploiting this vulnerability, according to CISA.
What to do
- Check which version of Microsoft Windows you run against the affected versions below, and install the vendor's latest release.
- CISA's required action: Apply updates per vendor instructions.
- Read the advisory on portal.msrc.microsoft.com for workarounds and exact fixed builds.
- Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Microsoft | Microsoft Windows | Not specified in the record | Not stated |
| Microsoft | Windows 10 1507 | Not specified in the record | Not stated |
| Microsoft | Windows 10 1511 | Not specified in the record | Not stated |
| Microsoft | Windows 10 1607 | Not specified in the record | Not stated |
| Microsoft | Windows 10 1703 | Not specified in the record | Not stated |
| Microsoft | Windows 7 | Not specified in the record | Not stated |
| Microsoft | Windows 8.1 | Not specified in the record | Not stated |
| Microsoft | Windows Rt 8.1 | Not specified in the record | Not stated |
| Microsoft | Windows Server 2008 | r2 | Not stated |
| Microsoft | Windows Server 2012 | r2 | Not stated |
| Microsoft | Windows Server 2016 | Not specified in the record | Not stated |
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- NetworkCan be exploited remotely over a network, including the internet.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- NoneNo account or login is needed.
- User interaction
- NoneNo action by a victim is required.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- HighAll data handled by the component can be read.
- Integrity
- HighData or code can be modified at will.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H. Scored by NVD.
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 3.1 | 9.8 | Critical | NVD |
| CVSS 3.1 | 9.8 | Critical | CISA (ADP) |
| CVSS 2.0 | 10.0 | High | NVD |
Official description
Microsoft Windows XP SP3, Windows XP x64 XP2, Windows Server 2003 SP2, Windows Vista, Windows 7 SP1, Windows Server 2008 SP2 and R2 SP1, Windows 8, Windows 8.1 and Windows RT 8.1, Windows Server 2012 and R2, Windows 10 Gold, 1511, 1607, and 1703, and Windows Server 2016 allow an attacker to take control of the affected system when Windows Search fails to handle objects in memory, aka "Windows Search Remote Code Execution Vulnerability".
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Improper Preservation of Permissions
The product does not preserve permissions or incorrectly preserves permissions when copying, restoring, or sharing objects, which can cause them to have less restrictive permissions than intended.
More Improper Preservation of Permissions vulnerabilities (CWE-281)
Timeline
- CVE record published.
- Added to CISA's Known Exploited Vulnerabilities catalogue.
- Deadline for US federal agencies to remediate, set by CISA.
- CISA published its SSVC assessment (exploitation: active, automatable: yes, technical impact: total).
- Record last changed materially (score, affected products, status or references).
References
Advisories
Third-party and government advisories
- cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2017-8543US Government Resource
Other vulnerabilities in Microsoft Windows
- 7.8 High severity
Microsoft Win32k Privilege Escalation Exploited
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