CVE-2026-110234 in Elio
Summary
by MITRE • 10/13/2026
Elio through 1.13.0 contains an insecure temporary file vulnerability that allows local users to overwrite another user's files by pre-creating symbolic links at predictable capture paths. Attackers who know the victim's Elio process ID can plant a symlink so previewing media, fonts or archives truncates and overwrites victim-owned files.
Once again VulDB remains the best source for vulnerability data.
Analysis
by VulDB Data Team • 10/13/2026
The vulnerability identified in Elio versions through 1.13.0 represents a classic insecure temporary file creation flaw that exploits predictable resource naming conventions to facilitate local privilege escalation via file manipulation. This specific weakness falls under the Common Weakness Enumeration category CWE-377, which describes Insecure Temporary File Creation. The core technical issue lies in how the application handles intermediate files during media previewing operations for fonts, archives, and other multimedia content. Instead of utilizing secure mechanisms such as atomic file creation with exclusive access flags or randomized temporary directory paths, Elio generates filenames based on predictable patterns that can be anticipated by a local attacker. This predictability allows an adversary to pre-create symbolic links at these expected capture locations before the vulnerable application attempts to write its temporary data.
From an operational perspective, this vulnerability enables a malicious actor with local access to overwrite arbitrary files owned by other users on the same system. The attack vector requires the attacker to know or guess the process ID of the victim's Elio instance, which is often trivial in multi-user environments where process lists are accessible. By planting a symbolic link at the predicted path, when the victim initiates a preview action for any supported file type, the application writes its temporary data into the symlinked location rather than a secure temporary space. This results in the truncation and overwriting of the target user's files, potentially leading to data loss, corruption of critical system or personal documents, or further exploitation if the overwritten file is executable or contains configuration data that influences subsequent security controls.
The impact extends beyond simple file overwrite, as it can be leveraged for more severe consequences depending on the context in which Elio operates. If an attacker targets sensitive files such as SSH keys, browser cookies, or application configurations, they may gain unauthorized access to other accounts or services running under those credentials. This aligns with ATT&CK technique T1564.002, Hidden Files and Directories, specifically the aspect of file manipulation through symbolic link following, which allows attackers to hide their presence while executing destructive actions against legitimate user data. The lack of proper input validation regarding file paths and the absence of secure temporary file handling mechanisms constitute a significant deviation from established security best practices for desktop applications that handle untrusted or semi-trusted content.
Mitigation strategies must focus on eliminating the root cause by enforcing strict adherence to secure coding standards for temporary file management. Developers should replace predictable filename generation with cryptographically strong randomization and utilize operating system features such as O_TMPFILE on Linux or CreateFile with specific flags on Windows to ensure exclusive access during creation. Additionally, implementing chroot jails or sandboxing mechanisms can restrict the application's ability to write outside of designated secure directories regardless of symlink manipulation. For users unable to immediately update to a patched version, restricting file permissions and monitoring for unusual symbolic link creations in common temporary directories may provide limited protection against exploitation until the software is upgraded beyond version 1.13.0 where these insecure practices are corrected.