CVE-2018-12918 in PBC
Summary
by MITRE
In libpbc.a in PBC through 2017-03-02, there is a Segmentation fault in _pbcB_register_fields in bootstrap.c.
If you want to get the best quality for vulnerability data then you always have to consider VulDB.
Analysis
by VulDB Data Team • 03/29/2023
The vulnerability identified as CVE-2018-12918 affects the PBC library version 2017-03-02 and earlier, specifically within the libpbc.a component. This issue manifests as a segmentation fault during the execution of the _pbcB_register_fields function located in bootstrap.c. The PBC library serves as a cryptographic library implementing pairing-based cryptography, which is widely used in various security applications including digital signatures, identity-based encryption, and secure multi-party computation protocols. The segmentation fault represents a critical stability issue that can lead to application crashes and potential denial of service conditions when the library processes malformed input data.
The technical flaw stems from inadequate input validation and memory management within the bootstrap.c file where the _pbcB_register_fields function attempts to register fields without proper bounds checking or error handling. This vulnerability falls under CWE-125, which describes out-of-bounds read conditions, and CWE-787, which covers out-of-bounds write conditions. The function likely processes field definitions from input data structures without verifying that the data conforms to expected formats or size constraints, leading to memory corruption when attempting to access invalid memory locations. This type of vulnerability is particularly dangerous in cryptographic libraries where memory corruption can potentially lead to more severe security implications beyond simple crashes.
The operational impact of this vulnerability extends beyond simple application instability, as it can be exploited by malicious actors to cause denial of service attacks against systems that rely on the PBC library. When a segmentation fault occurs during cryptographic operations, it can result in complete application termination, forcing system administrators to restart services and potentially disrupting legitimate user operations. The vulnerability affects any system running applications that utilize the affected PBC library version, particularly those implementing pairing-based cryptographic protocols such as identity-based encryption systems, short signature schemes, or advanced cryptographic protocols requiring bilinear pairings. Security professionals should be aware that this issue may be exploited in automated scanning tools or attack frameworks targeting systems with outdated cryptographic libraries.
Mitigation strategies for CVE-2018-12918 primarily involve upgrading to a patched version of the PBC library released after March 2017, which should include proper input validation and memory management controls. Organizations should conduct comprehensive vulnerability assessments to identify all systems utilizing the affected library version and prioritize patching efforts accordingly. The ATT&CK framework categorizes this vulnerability under T1499.004, which covers "Resource Hijacking: Unusual Privilege Gain," as exploitation could potentially allow attackers to consume system resources through repeated crash conditions. Additionally, implementing proper input sanitization and bounds checking in applications that interface with the PBC library can provide additional defense in depth measures. System administrators should also consider implementing monitoring solutions to detect unusual crash patterns that might indicate exploitation attempts, as the segmentation fault behavior could serve as an indicator of active attacks against vulnerable systems.