Microsoft PostScript Printer Driver Flaw CVSS 9.8 Requires Immediate Attention
A critical heap-based buffer overflow in the Microsoft PostScript Printer Driver allows unauthorized remote code execution, rated CVSS 9.8 by the NVD.
Key points
- The vulnerability is CVE-2026-70147, a heap-based buffer overflow in the Microsoft PostScript Printer Driver.
- The National Vulnerability Database rates the flaw as Critical with a CVSS score of 9.8.
- An unauthorized attacker can exploit this issue to execute code over a network.
Microsoft has issued an advisory for CVE-2026-70147, a remote code execution vulnerability in its PostScript Printer Driver. The National Vulnerability Database assigns this flaw a CVSS score of 9.8, categorizing it as Critical.
What happened
The Microsoft Security Update Guide describes CVE-2026-70147 as a heap-based buffer overflow within the Microsoft PostScript Printer Driver. This weakness allows an unauthorized attacker to execute code over a network. The National Vulnerability Database records the same technical description and assigns a CVSS base score of 9.8. The flaw is mapped to CWE-122, which identifies heap-based buffer overflows as the underlying weakness.
Why it matters
The National Vulnerability Database rates CVE-2026-70147 as Critical with a CVSS score of 9.8. The Microsoft Security Update Guide states that the flaw allows an unauthorized attacker to execute code over a network. This capability enables remote exploitation of systems running the affected driver. The high severity rating indicates the potential impact of the vulnerability on affected systems.
What to watch
- Monitor Microsoft Security Update Guide for new patch releases or advisory updates.
- Check internal logs for unusual print job activity or unexpected process creations.
- Verify that all systems are receiving updates from trusted Microsoft channels.
- Watch for any public disclosure of active exploitation related to CVE-2026-70147.
Who needs to act first
Teams should prioritize systems that are directly exposed to untrusted networks or handle print jobs from external users. Before applying any changes, administrators must verify that current backups are complete and valid. Testing the update in a non-production environment helps ensure that printer functionality remains stable after the fix is applied. If a patch is not yet available, limiting network access to print services reduces the attack surface significantly.
Background: CVSS score
The CVSS score explains vulnerability severity using a 0.0 to 10.0 scale. It measures attack vector, complexity, privileges required, and impact on confidentiality, integrity, and availability. You use this metric to prioritize patches, though you must adjust it for your specific environment to avoid wasting time on irrelevant threats.
Read the full guide: CVSS Score Explained: How to Read Risk Metrics and Prioritize Fixes
What to do and how to stay safe: Microsoft
- Audit your environment to identify all servers and workstations using the Microsoft PostScript Printer Driver.
- Isolate critical print servers from general network traffic if possible to limit remote access vectors.
- Enable detailed logging for printer services to detect any unauthorized code execution attempts.
- Prepare a deployment plan to apply the vendor update once it becomes available to all affected systems.
Step-by-step guide: Virtual Patching Myths: What It Actually Fixes and Breaks
General security guidance from the Patch Gazette newsroom. It is not confirmed advice from the organisations named in this story.
Frequently asked questions
What is the CVSS score for CVE-2026-70147?
The National Vulnerability Database rates CVE-2026-70147 with a CVSS score of 9.8, which is considered Critical.
Can this vulnerability be exploited remotely?
Yes, the Microsoft Security Update Guide states that an unauthorized attacker can execute code over a network.
What type of weakness is involved in this flaw?
The vulnerability is a heap-based buffer overflow, identified as CWE-122 in the NVD record.
