Description

A flaw was found in libdm. A remote attacker could craft a malicious Logical Volume Manager (LVM) metadata configuration with deeply nested structures. This could lead to uncontrolled recursion in the libdm configuration file parser, exhausting the stack and causing any LVM command reading the metadata to crash. This vulnerability results in a Denial of Service (DoS) for affected systems.

Executive Summary

Technical Details

Mitigations

References

Additional Metadata

{
  "score": "5.5",
  "pubDate": "2026-08-14T06:17:14.410Z",
  "pubdate": "2026-08-14T06:17:14.410Z",
  "executiveSummary": "A denial of service vulnerability exists within the libdm configuration file parser due to improper handling of deeply nested structures. The flaw is triggered when processing a maliciously crafted Logical Volume Manager (LVM) metadata configuration containing excessive nesting levels. This results in uncontrolled recursion during parsing, leading to stack exhaustion and the immediate crash of any LVM command that attempts to read the compromised metadata.\nThe affected product is libdm, impacting all systems utilizing vulnerable LVM components that parse untrusted metadata configurations. An attacker capable of supplying or modifying LVM metadata on a target system can induce a denial of service state, disrupting storage management operations and potentially rendering the underlying system unstable or inaccessible.\nExploitation of this vulnerability requires the ability to introduce or manipulate LVM metadata configurations processed by the affected parser. The risk implication is significant for systems that ingest external or untrusted storage configurations, as a successful crash of LVM commands can halt critical system administration tasks, automated storage provisioning, and boot sequences relying on logical volume activation.",
  "technicalDetails": "The root cause of the vulnerability resides in the configuration file parser implementation within libdm. Specifically, the parser fails to enforce limits or boundaries on the recursion depth when traversing hierarchical and nested structures defined within LVM metadata configurations.\nWhen libdm processes a configuration file containing maliciously constructed, deeply nested sections or directives, the recursive parsing functions repeatedly invoke themselves, consuming stack memory for each level of nesting without a terminating safeguard or depth counter.\nThe attack flow proceeds as follows: First, the threat actor crafts a specialized LVM metadata configuration file incorporating an excessively deep hierarchy of nested objects or blocks. Second, this malicious metadata is placed where it will be ingested by the system, such as on a storage medium, within a metadata backup, or supplied via an operational LVM interface. Third, an LVM command is executed on the target system that invokes libdm to read and parse the metadata structure. Fourth, as the parser traverses the nested configuration, the uncontrolled recursion rapidly exhausts the available call stack memory. Finally, the stack overflow triggers a segmentation fault or memory corruption exception, causing the LVM process to terminate abnormally, thereby achieving a denial of service.\nThe vulnerable component is the libdm configuration parser. Exploitation causes application-layer termination of LVM binaries and commands attempting to parse the input. The vulnerability does not inherently grant remote code execution based on the provided text, but results strictly in availability degradation through process crashes."
}