CVE-2023-25585: GNU Binutils DOS Vulnerability

CVE-2023-25585 Overview

A flaw was found in GNU Binutils where the use of an uninitialized field in the struct module *module may lead to application crash and local denial of service. This vulnerability is classified under CWE-457 (Use of Uninitialized Variable) and CWE-908 (Use of Uninitialized Resource), affecting the stability and reliability of development environments that rely on Binutils for compiling and linking operations.

Critical Impact

Exploitation of this vulnerability can cause application crashes and local denial of service conditions, potentially disrupting development workflows and build processes that depend on GNU Binutils.

Affected Products

• GNU Binutils 2.40
• Linux distributions shipping vulnerable Binutils versions
• Development environments using affected Binutils packages

Discovery Timeline

• 2023-09-14 - CVE-2023-25585 published to NVD
• 2024-11-21 - Last updated in NVD database

Technical Details for CVE-2023-25585

Vulnerability Analysis

This vulnerability stems from improper memory initialization within the GNU Binutils codebase. Specifically, a field within the struct module *module structure is used before being properly initialized. When Binutils processes certain inputs, the uninitialized memory can contain arbitrary or garbage values, leading to unpredictable behavior including application crashes.

The vulnerability requires local access and user interaction to exploit, as an attacker would need to provide a specially crafted input file to a Binutils utility. While the vulnerability does not impact data confidentiality or integrity, it can completely disrupt availability by causing the affected application to terminate unexpectedly.

Root Cause

The root cause of CVE-2023-25585 lies in the failure to properly initialize all fields of the struct module *module data structure before use. In C programming, uninitialized variables can contain residual data from previous memory operations. When the code attempts to read or dereference this uninitialized field, it may access invalid memory locations or interpret garbage values as valid pointers, resulting in segmentation faults or other crash conditions.

Attack Vector

The attack vector for this vulnerability is local, requiring an attacker to have access to the target system and convince a user to process a malicious file with a vulnerable Binutils tool. The exploitation scenario involves:

1. An attacker crafts a specially malformed binary file or object file
2. The victim processes this file using a vulnerable Binutils utility (such as objdump, readelf, or the linker ld)
3. The malformed input triggers a code path that references the uninitialized module field
4. The application crashes, resulting in denial of service

The vulnerability mechanism involves the uninitialized field in the module structure being accessed during file processing. When Binutils parses the crafted input, it reaches a code path that reads the uninitialized field, which may contain arbitrary values from prior memory operations. This leads to undefined behavior and ultimately causes the application to crash. For detailed technical analysis, refer to the Sourceware Bug Report.

Detection Methods for CVE-2023-25585

Indicators of Compromise

• Unexpected crashes of Binutils utilities such as objdump, readelf, nm, or ld
• Segmentation fault errors in system logs when processing binary files
• Repeated build failures or interruptions in automated build pipelines
• Core dumps generated by Binutils applications

Detection Strategies

• Monitor system logs for segmentation faults involving Binutils binaries
• Implement file integrity monitoring on critical development systems
• Use static analysis tools to scan for potentially malicious binary files before processing
• Deploy endpoint detection to identify unusual Binutils process terminations

Monitoring Recommendations

• Enable core dump collection and analysis for Binutils processes in development environments
• Implement alerting on abnormal termination patterns for build-related processes
• Monitor for suspicious binary files being introduced into build pipelines
• Track Binutils version deployments across the organization to identify vulnerable installations

How to Mitigate CVE-2023-25585

Immediate Actions Required

• Update GNU Binutils to a patched version that addresses the uninitialized memory issue
• Review and update Linux distribution packages that include Binutils
• Audit development environments for vulnerable Binutils installations
• Implement input validation for untrusted binary files in build pipelines

Patch Information

The fix for this vulnerability is available in the Sourceware Git repository. The patch ensures proper initialization of the module structure fields before use. Organizations should apply vendor-provided patches from their Linux distributions or update to a fixed Binutils release.

Additional advisory information is available from:

• Red Hat Security Advisory
• Red Hat Bugzilla
• NetApp Security Advisory

Workarounds

• Restrict processing of untrusted binary files with Binutils utilities
• Implement sandboxing or containerization for build processes handling external inputs
• Use file validation and scanning before processing binary files from untrusted sources
• Consider using alternative toolchains temporarily while patching is in progress

# Check installed Binutils version
ld --version
objdump --version

# On Debian/Ubuntu systems, update Binutils
sudo apt update && sudo apt upgrade binutils

# On RHEL/CentOS systems, update Binutils
sudo yum update binutils

# On Fedora systems, update Binutils
sudo dnf update binutils