CVE-2026-112938
Description
A flaw was found in filelock. A local attacker with write access to a shared directory can exploit a timing race condition to substitute a lock directory with a symbolic link. This flaw primarily allows an attacker to cause a Denial of Service (DoS) by stranding lock files in other lock locations, causing legitimate processes to time out when attempting to acquire locks. Additionally, this issue may lead to unauthorized file creation or minor information disclosure through error messages.
Statement
This vulnerability is rated as Moderate impact for Red Hat because exploitation requires an unprivileged local user to win a time-of-check to time-of-use race condition, and the impact is confined to lock contention, localized denial of service, or minimal information leakage rather than system compromise. In standard Red Hat enterprise deployments, automated services and workloads typically isolate lock targets within user-owned or restricted-access directories where untrusted accounts cannot alter intermediate filesystem components. Consequently, the issue only presents a practical risk on multi-user systems where applications are explicitly configured to place strict file locks inside shared or world-writable directory trees.
Mitigation
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.
Understanding the Weakness (CWE)
Integrity,Other
Technical Impact: Alter Execution Logic; Unexpected State
The attacker can gain access to otherwise unauthorized resources.
Integrity,Other
Technical Impact: Modify Application Data; Modify Files or Directories; Modify Memory; Other
Race conditions such as this kind may be employed to gain read or write access to resources which are not normally readable or writable by the user in question.
Integrity,Other
Technical Impact: Other
The resource in question, or other resources (through the corrupted one), may be changed in undesirable ways by a malicious user.
Non-Repudiation
Technical Impact: Hide Activities
If a file or other resource is written in this method, as opposed to in a valid way, logging of the activity may not occur.
Non-Repudiation,Other
Technical Impact: Other
In some cases it may be possible to delete files a malicious user might not otherwise have access to, such as log files.
Other
Technical Impact: Unexpected State
The product may perform invalid actions when the resource is in an unexpected state.
Frequently Asked Questions
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