CVE-2018-18700 in binutils
Summary
by MITRE
An issue was discovered in cp-demangle.c in GNU libiberty, as distributed in GNU Binutils 2.31. There is a stack consumption vulnerability resulting from infinite recursion in the functions d_name(), d_encoding(), and d_local_name() in cp-demangle.c. Remote attackers could leverage this vulnerability to cause a denial-of-service via an ELF file, as demonstrated by nm.
If you want to get best quality of vulnerability data, you may have to visit VulDB.
Analysis
by VulDB Data Team • 06/03/2023
The vulnerability identified as CVE-2018-18700 represents a critical stack consumption flaw within the GNU libiberty library component of GNU Binutils 2.31. This issue manifests in the cp-demangle.c file where recursive function calls can lead to unbounded stack growth during the processing of certain ELF files. The vulnerability specifically affects the d_name(), d_encoding(), and d_local_name() functions which form part of the C++ symbol demangling functionality. When these functions encounter malformed or specially crafted input, they can trigger infinite recursion patterns that rapidly consume system stack memory resources.
The technical implementation of this vulnerability stems from inadequate input validation and boundary checking within the demangling algorithms. The functions in question are designed to parse and reconstruct C++ symbol names from their mangled representations, but they fail to properly terminate recursive calls when encountering complex or malformed symbol structures. This recursive behavior becomes particularly dangerous when processing ELF files that contain crafted symbol tables, as the demangling process can spiral into infinite loops. The vulnerability is particularly concerning because it operates at the binary parsing level where attackers can leverage it through standard tools like nm, which is commonly used for symbol table examination and analysis.
The operational impact of CVE-2018-18700 extends beyond simple denial-of-service conditions, as it can effectively crash any application or tool that relies on GNU libiberty for symbol demangling operations. Attackers can exploit this weakness by constructing malicious ELF files that contain specially formatted symbol entries designed to trigger the recursive behavior. When such files are processed by tools that utilize the vulnerable demangling functions, the system stack becomes exhausted, leading to process termination and complete service unavailability. This vulnerability is classified under CWE-674 as "Uncontrolled Recursion" and represents a classic example of a stack overflow condition that can be triggered without requiring elevated privileges. The attack surface includes any system that processes ELF files through tools built on GNU Binutils, making it particularly dangerous in environments where automated symbol processing is common.
Mitigation strategies for this vulnerability primarily involve upgrading to patched versions of GNU Binutils where the recursive calls have been properly bounded and validated. The fix typically implements stack depth monitoring and maximum recursion limits within the demangling functions to prevent uncontrolled expansion. Security practitioners should also implement input validation measures when processing external ELF files, particularly in automated analysis systems. Organizations should conduct vulnerability assessments to identify systems running vulnerable versions of binutils and prioritize patch deployment. The ATT&CK framework categorizes this as a privilege escalation technique through resource exhaustion, where attackers leverage software weaknesses to consume system resources and disrupt normal operations. Additional protective measures include implementing sandboxing for ELF file analysis, monitoring system stack usage patterns, and establishing automated alerting for unusual memory consumption behaviors that may indicate exploitation attempts.