CVE-2024-27280 is a critical-severity (CVSS 9.8) CWE-120 vulnerability in stringio. A fix is available for stringio — see the affected versions and patch details below.
StringIO buffer overread vulnerability
Exploitation Status
No confirmed exploitation observed yet
- CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
- A successful exploit gives an attacker total control of the affected component, not partial access.
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2024-27280.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
Where this sits among everything scored
Real-World Exposure
stringioReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects RubyGems packages — download data is not available via public APIs for these ecosystems.
Description
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.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 💎RubyGems | stringio | all versions | 3.0.1.1bundle update stringio --conservative |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for stringio, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update stringio to 3.0.1.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2024-27280 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
Fixing This On Your OS
If you run this on a Linux distribution, patch through your package manager against the distro's own security advisory below — it tracks the exact backported fix for your release, which can ship on a different timeline (and sometimes a different severity) than the upstream project.
Mitigation for this issue is either not available or the currently available options don't meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.Source: Red Hat security advisory for CVE-2024-27280 (CC BY 4.0)
| Product | Fixed in | Advisory |
|---|---|---|
| Red Hat Enterprise Linux 8 | ruby:3.0-8100020240522072634.489197e6 | RHSA-2024:3500 |
| Red Hat Enterprise Linux 8 | ruby:3.1-8100020240510101534.489197e6 | RHSA-2024:3546 |
| Red Hat Enterprise Linux 8 | ruby:3.3-8100020240522151542.489197e6 | RHSA-2024:3670 |
| Red Hat Enterprise Linux 8 | ruby:2.5-8100020240627152904.489197e6 | RHSA-2024:4499 |
| Red Hat Enterprise Linux 9 | ruby:3.1-9040020240503183840.9 | RHSA-2024:3668 |
| Red Hat Enterprise Linux 9 | ruby:3.3-9040020240522171337.9 | RHSA-2024:3671 |
| Red Hat Enterprise Linux 9 | ruby-0:3.0.7-162.el9_4 | RHSA-2024:3838 |
Frequently Asked Questions
Is CVE-2024-27280 in your dependencies?
Find it across RubyGems, including transitive dependencies.