Description
A buffer-overread 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. 3.0.3 is the main fixed version; however, for Ruby 3.0 users, a fixed version is stringio 3.0.1.1, and for Ruby 3.1 users, a fixed version is stringio 3.0.1.2.
EPSS Score:
1%
Comprehensive Technical Analysis of EUVD-2024-1008
1. Vulnerability Assessment and Severity Evaluation
The vulnerability described in EUVD-2024-1008 pertains to a buffer-overread issue in the StringIO library, specifically in versions 3.0.1 as distributed in Ruby 3.0.x through 3.0.6 and 3.1.x through 3.1.4. This vulnerability allows the ungetbyte and ungetc methods to read past the end of a string, potentially exposing memory values when StringIO.gets is subsequently called.
Severity Evaluation:
- Base Score: 9.8 (CVSS 3.1)
- Vector String: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
The high base score indicates a critical vulnerability due to the following factors:
- Attack Vector (AV:N): Network exploitable.
- Attack Complexity (AC:L): Low complexity required for exploitation.
- Privileges Required (PR:N): No privileges are required.
- User Interaction (UI:N): No user interaction is required.
- Scope (S:U): Unchanged.
- Confidentiality (C:H), Integrity (I:H), Availability (A:H): High impact on all three CIA triad components.
2. Potential Attack Vectors and Exploitation Methods
Attack Vectors:
- Remote Exploitation: An attacker could exploit this vulnerability over the network by sending crafted input to a Ruby application that uses the affected StringIO library.
- Local Exploitation: A malicious user with local access could exploit this vulnerability to read sensitive memory contents.
Exploitation Methods:
- Memory Disclosure: By crafting specific inputs that trigger the buffer-overread, an attacker can read memory contents, potentially exposing sensitive information such as cryptographic keys, passwords, or other confidential data.
- Code Execution: Although not directly mentioned, the exposure of memory contents could be leveraged in conjunction with other vulnerabilities to achieve arbitrary code execution.
3. Affected Systems and Software Versions
Affected Software:
- Ruby 3.0.x: Versions 3.0.1 through 3.0.6
- Ruby 3.1.x: Versions 3.0.1 through 3.1.4
Fixed Versions:
- Ruby 3.0: Fixed in StringIO 3.0.1.1
- Ruby 3.1: Fixed in StringIO 3.0.1.2
4. Recommended Mitigation Strategies
Immediate Actions:
- Update Software: Upgrade to the patched versions of StringIO:
- For Ruby 3.0 users: Update to StringIO 3.0.1.1
- For Ruby 3.1 users: Update to StringIO 3.0.1.2
- Monitoring: Implement monitoring for unusual memory access patterns and anomalous behavior in applications using the StringIO library.
Long-Term Strategies:
- Code Review: Conduct thorough code reviews to identify and mitigate similar buffer-overread issues in other parts of the codebase.
- Security Training: Educate developers on secure coding practices to prevent such vulnerabilities in future releases.
- Regular Updates: Ensure that all software dependencies are regularly updated to their latest versions.
5. Impact on European Cybersecurity Landscape
The vulnerability poses a significant risk to organizations and individuals using the affected versions of Ruby, particularly those in the European Union. The high severity score and the potential for remote exploitation make it a critical concern for cybersecurity professionals. Organizations should prioritize patching and monitoring to mitigate the risk of data breaches and potential compliance issues under regulations such as GDPR.
6. Technical Details for Security Professionals
Vulnerability Details:
- CVE ID: CVE-2024-27280
- GHSA ID: GHSA-v5h6-c2hv-hv3r
- Affected Methods:
ungetbyte,ungetc, andStringIO.gets - Root Cause: Improper bounds checking in the StringIO library, allowing reads past the end of a string.
References:
- NVD Entry: CVE-2024-27280
- GitHub Commits:
- HackerOne Report: Report 1399856
- Ruby Advisory DB: CVE-2024-27280.yml
- Ruby News: Buffer Overread CVE-2024-27280
Conclusion: This vulnerability underscores the importance of regular software updates and thorough security testing. Organizations should act promptly to mitigate the risk and ensure the security of their systems.