Vim: Out-of-bounds Read in Terminal Screen Snapshot_CVE-2026-52859

6.9 / 10

MEDIUM

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:L/SC:N/SI:N/SA:N

Description

Vim is an open source, command line text editor. Prior to version 9.2.0565, the update_snapshot() function in src/terminal.c copies the visible terminal screen into the scrollback buffer when a snapshot is taken. For each screen cell it walks the cell's chars[] array with no upper bound, stopping only when it encounters a NUL terminator. When a cell legitimately fills all VTERM_MAX_CHARS_PER_CELL (6) slots — a base character plus five combining marks — the bundled libvterm returns the array without a terminating NUL, so the loop reads past the fixed six-element array and appends the out-of-bounds values to a buffer reserved for only six characters. A program whose output is rendered inside a :terminal window can trigger this with a short byte sequence and no Vim scripting, leading to a crash. This issue has been patched in version 9.2.0565.

Basic Information

ID CVE-2026-52859

Source GitHub_M

Published Jun 11, 2026 at 18:33

Affected Product

Vendor vim

Product vim

Version < 9.2.0565

Affected Versions vim vim < 9.2.0565

CWE Classification

CWE-125

References

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    "published": "2026-06-11T18:33:09.886Z",
    "modified": "2026-06-11T18:33:09.886Z",
    "type": "cve",
    "title": "Vim: Out-of-bounds Read in Terminal Screen Snapshot",
    "source": "GitHub_M",
    "references": "https://github.com/vim/vim/security/advisories/GHSA-47gw-8gc3-mgcm\nhttps://github.com/vim/vim/commit/63680c6d3d52477817b49cd1a66e7aabe8a7aa19\nhttps://github.com/vim/vim/releases/tag/v9.2.0565",
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