Out-of-bounds read in Vim - #VU133141

Detailed vulnerability description

The vulnerability allows a local user to cause a denial of service.

The vulnerability exists due to out-of-bounds read in the update_snapshot() function in src/terminal.c when processing terminal screen snapshots in a :terminal window. A local user can emit terminal output containing a cell with a base character and five combining marks to cause a denial of service.

The issue can be triggered when the user enters Terminal-Normal mode or when the terminal job exits.

Remediation

Sources

• https://github.com/vim/vim/security/advisories/GHSA-47gw-8gc3-mgcm
• https://github.com/vim/vim/commit/63680c6d3d52477817b49cd1a66e7aabe8a7aa19