CVE-2026-52859

Severity CVSS v4.0:

MEDIUM

Type:

CWE-125 Out-of-bounds Read

Publication date:

11/06/2026

Last modified:

15/06/2026

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&#39;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.

Impact

Vector 4.0

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 CVSS v4.0 Severity and Metrics:

Base Score: 6.90 MEDIUM
Vector: 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

Attack Vector (AV): Network
Attack Complexity (AC): Low
Attack Requirements (AT): None
Privileges Required (PR): None
User Interaction (UI): None
Confidentiality (VC): Low
Integrity (VI): None
Availability (VA): Low
Confidentiality (SC): None
Integrity (SI): None
Availability (SA): None

Base Score 4.0

6.90

Severity 4.0

MEDIUM

Vector 3.x

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:H CVSS v3.1 Severity and Metrics:

Base Score: 8.20 HIGH
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:H

Attack Vector (AV): Network
Attack Complexity (AC): Low
Privileges Required (PR): None
User Interaction (UI): None
Scope (S): Unchanged
Confidentiality (C): Low
Integrity (I): None
Availability (A): High