The vulnerability CVE-2025-9810 affects the linenoise library by antirez, specifically in the linenoiseHistorySave function. It arises from a TOCTOU race condition where an attacker can create a symbolic link to a target file. When linenoise opens the history file with fopen("w") and then changes its permissions with chmod(), the attacker can exploit the timing window to overwrite arbitrary files and alter their permissions. This can lead to integrity issues on the affected system. The vulnerability requires local access and does not involve user interaction or privileges beyond local access.

Successful exploitation allows a local attacker to overwrite arbitrary files and change their permissions, potentially leading to unauthorized modification of files and privilege escalation scenarios. The impact is limited to integrity and availability with no confidentiality impact reported. The CVSS vector indicates low attack complexity and no privileges required, but local access is necessary.

Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Since no patch or official fix is currently available, users should monitor vendor communications for updates. Until a fix is released, restricting local access to trusted users and avoiding use of vulnerable linenoise versions in sensitive environments is recommended.