Buffer overflow in Vim
CVE-2026-28420
Vim is an open source, command line text editor. Prior to version 9.2.0076, a heap-based buffer overflow WRITE and an out-of-bounds READ exist in Vim's terminal emulator when processing maximum combining characters from Unicode supplementary planes. Version 9.2.0076 fixes the issue.
Vulnerability class: Buffer Overflow
EPSS: 0.002 (7.5th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 4.4 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:L.
Affected products
- Vim — versions < 9.2.0076
Weakness classification (CWE)
References
- security-advisories@github.com (x_refsource_CONFIRM, Patch, Vendor Advisory)
- security-advisories@github.com (Patch, x_refsource_MISC)
- security-advisories@github.com (Product, x_refsource_MISC)
- af854a3a-2127-422b-91ae-364da2661108 (Mailing List, Patch, Third Party Advisory)
Frequently asked questions
- What is CVE-2026-28420?
- CVE-2026-28420 is a medium-severity vulnerability in Vim, classified under Heap-based Buffer Overflow. CVSS score: 4.4/10. Published 2026-02-27.
- How severe is CVE-2026-28420?
- Medium severity. CVSS v3 base score is 4.4 out of 10.