Microsoft SQL Server Reporting Services Remote Code Execution
CVE-2020-0618 is a high-severity deserialization of untrusted data vulnerability in Microsoft SQL Server from Microsoft, with a CVSS 3.1 base score of 8.8 out of 10. It can be exploited remotely over the network by an attacker with a low-privileged account, without any action from a user. Affected Microsoft SQL Server versions: 2012 for 32-bit Systems Service Pack 4 (QFE); 2012 for x64-based Systems Service Pack 4 (QFE); 2016 for x64-based Systems Service Pack 2 (CU). The record does not name a fixed version, so check the vendor advisory. CISA added it to the Known Exploited Vulnerabilities catalogue on September 18, 2024, which means attacks have been observed in the wild, including in ransomware campaigns.
Attackers are already exploiting this vulnerability, according to CISA.
What to do
- Check which version of Microsoft SQL Server you run against the affected versions below, and install the vendor's latest release.
- CISA's required action: Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.
- Read the advisory on portal.msrc.microsoft.com for workarounds and exact fixed builds.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Microsoft | Microsoft SQL Server | 2012 for 32-bit Systems Service Pack 4 (QFE); 2012 for x64-based Systems Service Pack 4 (QFE); 2016 for x64-based Systems Service Pack 2 (CU) | Not stated |
| Microsoft | Microsoft SQL Server 2014 Service Pack 3 for x64-based Systems (GDR) | Not specified in the record | Not stated |
| Microsoft | Microsoft SQL Server 2014 Service Pack 3 for x64-based Systems (CU) | Not specified in the record | Not stated |
| Microsoft | Microsoft SQL Server 2016 for x64-based Systems Service Pack 2 (GDR) | Not specified in the record | Not stated |
| Microsoft | Microsoft SQL Server 2014 Service Pack 3 for 32-bit Systems (GDR) | Not specified in the record | Not stated |
| Microsoft | Microsoft SQL Server 2014 Service Pack 3 for 32-bit Systems (CU) | Not specified in the record | Not stated |
| Microsoft | SQL Server | 2012; 2014; 2016 | 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
- LowA basic user account is enough.
- 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:L/UI:N/S:U/C:H/I:H/A:H. Scored by NVD.
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 3.1 | 8.8 | High | NVD |
| CVSS 3.1 | 9.8 | Critical | CISA (ADP) |
| CVSS 2.0 | 6.5 | Medium | NVD |
Official description
A remote code execution vulnerability exists in Microsoft SQL Server Reporting Services when it incorrectly handles page requests, aka 'Microsoft SQL Server Reporting Services Remote Code Execution Vulnerability'.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Deserialization of Untrusted Data
The product deserializes untrusted data without sufficiently ensuring that the resulting data will be valid.
How developers prevent this class of flaw
- If available, use the signing/sealing features of the programming language to assure that deserialized data has not been tainted. For example, a hash-based message authentication code (HMAC) could be used to ensure that data has not been modified.
- When deserializing data, populate a new object rather than just deserializing. The result is that the data flows through safe input validation and that the functions are safe.
- Explicitly define a final object() to prevent deserialization.
More Deserialization of Untrusted Data vulnerabilities (CWE-502)
Timeline
- CVE record published.
- Added to CISA's Known Exploited Vulnerabilities catalogue.
- CISA published its SSVC assessment (exploitation: active, automatable: no, technical impact: total).
- Deadline for US federal agencies to remediate, set by CISA.
- Record last changed materially (score, affected products, status or references).
References
Third-party and government advisories
- cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2020-0618US Government Resource
Technical write-ups (may include proof of concept)
- packetstormsecurity.com/files/156707/SQL-Server-Reporting-Services-SSRS-ViewState-Deserialization.htmlExploit, Third Party Advisory, VDB Entry
- packetstormsecurity.com/files/159216/Microsoft-SQL-Server-Reporting-Services-2016-Remote-Code-Execution.htmlExploit, Third Party Advisory, VDB Entry
Other vulnerabilities in Microsoft SQL Server
- 8.8 High severity
Recent Deserialization of Untrusted Data vulnerabilities
- 9.8 Critical severity
- 9.8 Critical severity
- 8.8 High severity
- 9.8 Critical severity
- 8.8 High severity
- 9.8 Critical severity
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