CVE-2024-27280
📋 TL;DR
This CVE describes a buffer-overread vulnerability in Ruby's StringIO library where the ungetbyte and ungetc methods can read past string boundaries, potentially exposing memory contents. This affects Ruby 3.0.x through 3.0.6 and 3.1.x through 3.1.4. Attackers could exploit this to leak sensitive memory data from applications using StringIO.
💻 Affected Systems
- Ruby
- StringIO gem
⚠️ Manual Verification Required
This CVE does not have specific version information in our database, so automatic vulnerability detection cannot determine if your system is affected.
Why? The CVE database entry doesn't specify which versions are vulnerable (no version ranges provided by the vendor/NVD).
🔒 Custom verification scripts are available for registered users. Sign up free to download automated test scripts.
- Review the CVE details at NVD
- Check vendor security advisories for your specific version
- Test if the vulnerability is exploitable in your environment
- Consider updating to the latest version as a precaution
⚠️ Risk & Real-World Impact
Worst Case
Memory disclosure leading to exposure of sensitive data like passwords, encryption keys, or application secrets, potentially enabling further attacks.
Likely Case
Information disclosure where attackers can read adjacent memory contents, potentially exposing application data or system information.
If Mitigated
Limited impact with proper input validation and memory isolation, though the vulnerability still exists at the library level.
🎯 Exploit Status
Exploitation requires specific method calls but is straightforward once identified in vulnerable code.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: StringIO 3.0.1.1 for Ruby 3.0, StringIO 3.0.1.2 for Ruby 3.1
Vendor Advisory: https://www.ruby-lang.org/en/news/2024/03/21/buffer-overread-cve-2024-27280/
Restart Required: Yes
Instructions:
1. Update Ruby to version 3.0.7+ or 3.1.5+. 2. Alternatively, update the stringio gem: 'gem update stringio'. 3. Restart all Ruby applications and services.
🔧 Temporary Workarounds
Avoid vulnerable StringIO methods
allTemporarily avoid using ungetbyte and ungetc methods on StringIO objects in your code.
# Code review to identify and modify usage of StringIO#ungetbyte and StringIO#ungetc
🧯 If You Can't Patch
- Implement strict input validation and sanitization for all StringIO inputs
- Isolate Ruby applications using containerization or virtualization to limit potential memory exposure
🔍 How to Verify
Check if Vulnerable:
Check Ruby version with 'ruby -v' and stringio gem version with 'gem list stringio'. If Ruby is 3.0.0-3.0.6 or 3.1.0-3.1.4, you are vulnerable.Check Version:
ruby -v && gem list stringioVerify Fix Applied:
After updating, verify with 'ruby -v' shows 3.0.7+ or 3.1.5+, and 'gem list stringio' shows 3.0.1.1+ for Ruby 3.0 or 3.0.1.2+ for Ruby 3.1.📡 Detection & Monitoring
Log Indicators:
- Unusual memory access patterns or crashes in Ruby applications using StringIO
Network Indicators:
- Unexpected data exfiltration from Ruby applications
SIEM Query:
source="ruby_app" AND (event="segmentation_fault" OR event="memory_error")🔗 References
- https://hackerone.com/reports/1399856
- https://www.ruby-lang.org/en/news/2024/03/21/buffer-overread-cve-2024-27280/
- http://seclists.org/fulldisclosure/2025/Sep/53
- http://seclists.org/fulldisclosure/2025/Sep/54
- http://seclists.org/fulldisclosure/2025/Sep/55
- https://hackerone.com/reports/1399856
- https://lists.debian.org/debian-lts-announce/2024/09/msg00000.html
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/27LUWREIFTP3MQAW7QE4PJM4DPAQJWXF/
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/XYDHPHEZI7OQXTQKTDZHGZNPIJH7ZV5N/
- https://security.netapp.com/advisory/ntap-20250502-0003/
- https://www.ruby-lang.org/en/news/2024/03/21/buffer-overread-cve-2024-27280/
