CVE-2025-27830
📋 TL;DR
A buffer overflow vulnerability in Artifex Ghostscript allows attackers to execute arbitrary code or cause denial of service by processing maliciously crafted font files. This affects systems using Ghostscript for PDF/PostScript processing, including document viewers, printers, and web applications that convert documents. The vulnerability is triggered during DollarBlend serialization in specific font handling functions.
💻 Affected Systems
- Artifex Ghostscript
📦 What is this software?
Ghostscript by Artifex
⚠️ Risk & Real-World Impact
Worst Case
Remote code execution with the privileges of the Ghostscript process, potentially leading to full system compromise.
Likely Case
Denial of service through application crashes when processing malicious documents.
If Mitigated
Limited impact if Ghostscript runs in sandboxed environments with minimal privileges.
🎯 Exploit Status
Exploitation requires crafting a malicious font file and getting it processed by Ghostscript. No public exploits are known as of the advisory.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 10.05.0
Vendor Advisory: https://bugs.ghostscript.com/show_bug.cgi?id=708241
Restart Required: No
Instructions:
1. Download Ghostscript 10.05.0 or later from https://www.ghostscript.com/. 2. Compile and install following the vendor's instructions. 3. For package managers: Use 'apt-get update && apt-get upgrade ghostscript' on Debian/Ubuntu or equivalent on other distributions.
🔧 Temporary Workarounds
Disable vulnerable font processing
allConfigure Ghostscript to disable DollarBlend font processing via command-line flags or configuration files.
gs -dNO_DOLLAR_BLEND -sDEVICE=... input.ps
🧯 If You Can't Patch
- Restrict Ghostscript to process only trusted documents from verified sources.
- Run Ghostscript in a sandboxed environment with minimal privileges and network access.
🔍 How to Verify
Check if Vulnerable:
Check Ghostscript version with 'gs --version'. If version is below 10.05.0, the system is vulnerable.Check Version:
gs --versionVerify Fix Applied:
After patching, run 'gs --version' to confirm version is 10.05.0 or higher.📡 Detection & Monitoring
Log Indicators:
- Ghostscript crash logs with segmentation faults
- Error messages mentioning write_t1.c or zfapi.c
Network Indicators:
- Unusual document uploads to web applications using Ghostscript
SIEM Query:
source="ghostscript.log" AND ("segmentation fault" OR "buffer overflow")