CVE-2017-9043 in binutils
Summary
by MITRE
readelf.c in GNU Binutils 2017-04-12 has a "shift exponent too large for type unsigned long" issue, which might allow remote attackers to cause a denial of service (application crash) or possibly have unspecified other impact via a crafted ELF file.
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Analysis
by VulDB Data Team • 12/04/2024
The vulnerability identified as CVE-2017-9043 resides within the readelf.c component of GNU Binutils, specifically affecting versions released on April 12, 2017. This issue manifests as a critical flaw in the handling of shift operations when processing ELF (Executable and Linkable Format) files, creating a scenario where an attacker can manipulate the shift exponent value beyond the maximum representable range for unsigned long data types. The vulnerability operates at the binary analysis level where readelf, a utility designed to display information about ELF files, encounters malformed input that triggers undefined behavior during arithmetic operations.
The technical root cause of this vulnerability stems from inadequate input validation and bounds checking within the shift operation implementation. When readelf processes a crafted ELF file containing maliciously constructed shift exponent values, it attempts to perform bitwise shift operations using values that exceed the capacity of the unsigned long data type. This condition leads to integer overflow or underflow scenarios that can corrupt memory structures or cause the application to terminate abruptly. The flaw represents a classic example of improper handling of arithmetic operations and demonstrates weaknesses in defensive programming practices that should prevent such conditions from occurring in security-critical applications.
The operational impact of this vulnerability extends beyond simple denial of service to potentially enable more sophisticated attack vectors. Remote attackers can exploit this weakness by crafting specially formatted ELF files that, when processed by readelf, will cause the application to crash and terminate unexpectedly. This creates a reliable denial of service condition that can be leveraged to disrupt legitimate system operations or services that depend on binutils functionality. The vulnerability's potential for unspecified other impacts suggests that under certain conditions, the memory corruption could potentially lead to more severe consequences including arbitrary code execution, though this has not been definitively confirmed in the public records.
Organizations utilizing GNU Binutils and related tools must implement immediate mitigation strategies to address this vulnerability. The primary recommendation involves updating to patched versions of GNU Binutils where the shift exponent validation has been properly implemented to prevent values from exceeding the maximum representable range. System administrators should also consider implementing file validation controls that prevent processing of suspicious ELF files or restrict access to binutils utilities from untrusted sources. Additional defensive measures include deploying runtime monitoring to detect anomalous behavior patterns and implementing network segmentation to limit the potential attack surface. The vulnerability aligns with CWE-191, Integer Underflow or Wraparound, and represents a pathway for adversaries to achieve persistent denial of service conditions as outlined in ATT&CK technique T1499.1, Network Denial of Service. Regular security assessments should include verification of binutils installations to ensure that all systems are running patched versions that address this specific vulnerability and prevent exploitation attempts.