CVE-2024-27280: StringIO buffer overread vulnerability
An issue was discovered in StringIO 3.0.1, as distributed in Ruby 3.0.x through 3.0.6 and 3.1.x through 3.1.4. The ungetbyte and ungetc methods on a StringIO can read past the end of a string, and a subsequent call to StringIO.gets may return the memory value. This vulnerability is not affected StringIO 3.0.3 and later, and Ruby 3.2.x and later. We recommend to update the StringIO gem to version 3.0.3 or later.
Published Mar 25, 2024 · Updated Nov 4, 2025
Affected packages
stringio
- Ecosystem
- RubyGems
- Affected
- < 3.0.1.1
- Fixed in
- 3.0.1.1
- Check
bundle info stringio
Advisory details
From the GitHub Advisory Database (CC BY 4.0).
An issue was discovered in StringIO 3.0.1, as distributed in Ruby 3.0.x through 3.0.6 and 3.1.x through 3.1.4.
The ungetbyte and ungetc methods on a StringIO can read past the end of a string, and a subsequent call to StringIO.gets may return the memory value.
This vulnerability is not affected StringIO 3.0.3 and later, and Ruby 3.2.x and later.
We recommend to update the StringIO gem to version 3.0.3 or later. In order to ensure compatibility with bundled version in older Ruby series, you may update as follows instead:
- For Ruby 3.0 users: Update to
stringio3.0.1.1 - For Ruby 3.1 users: Update to
stringio3.1.0.2
You can use gem update stringio to update it. If you are using bundler, please add gem "stringio", ">= 3.0.1.2" to your Gemfile.
References
- https://github.com/ruby/stringio/commit/0e596524097706263d10900ca180898e4a8f5233
- https://github.com/ruby/stringio/commit/c58c5f54f1eab99665ea6a161d29ff6a7490afc8
- https://github.com/rubysec/ruby-advisory-db/blob/master/gems/stringio/CVE-2024-27280.yml
- https://www.ruby-lang.org/en/news/2024/03/21/buffer-overread-cve-2024-27280
- https://nvd.nist.gov/vuln/detail/CVE-2024-27280
- https://hackerone.com/reports/1399856
- https://security.netapp.com/advisory/ntap-20250502-0003
- https://lists.debian.org/debian-lts-announce/2024/09/msg00000.html
- https://lists.fedoraproject.org/archives/list/[email protected]/message/27LUWREIFTP3MQAW7QE4PJM4DPAQJWXF
- https://lists.fedoraproject.org/archives/list/[email protected]/message/XYDHPHEZI7OQXTQKTDZHGZNPIJH7ZV5N
- https://github.com/advisories/GHSA-v5h6-c2hv-hv3r
How this page is made: the data panel comes from the GitHub Advisory Database, CISA’s KEV catalog, the NVD and FIRST EPSS, and updates twice a day. No analysis has been written for this entry yet. Methodology
