CVE-2026-55892

A flaw was found in Vim, an open-source command-line text editor. A remote attacker could exploit this vulnerability by convincing a user to load a specially crafted spell file. This malicious file can trigger a stack out-of-bounds write, which corrupts the editor's memory and causes it to crash. This leads to a Denial of Service (DoS), making the editor unavailable to the user.

A flaw was found in Vim's spell file handling. The dump_prefixes() function in src/spell.c does not validate the depth of the prefix trie against the size of fixed-size stack arrays, allowing a crafted .spl file to cause a stack out-of-bounds write and crash. Red Hat ships Vim in all RHEL versions and OpenShift CoreOS. Exploitation requires a user to load a malicious spell file and run :spelldump or spelling completion.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.

Do not load untrusted spell files (.spl) from unknown sources. Avoid using :spelldump with spell files of unknown provenance.