CVE-2026-28420 | Vim has Heap-based Buffer Overflow and OOB Read in :terminal

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.

Published: 2026-02-27 Last update: 2026-03-04 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2026-28420 is rated Low Risk (20.4/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.18%). Mandatory action: Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2026-28420

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.00% 0.18% +0.17%
2 2026-02-28 0.00%

Full EPSS history (2 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-28420

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
4.4 3.1 MEDIUM
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:L Click to expand
Attack vector (AV:L)
They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:L)
Might cause slowdowns, glitches, or partial disruption—not a full brick.
1.8 2.5 [email protected]
4.4 3.1 MEDIUM
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:L Click to expand
Attack vector (AV:L)
They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:L)
Might cause slowdowns, glitches, or partial disruption—not a full brick.
1.8 2.5 [email protected]

Weakness enumeration for CVE-2026-28420

OS Trackers for CVE-2026-28420

vendor priority summary link
alpine CVE-2026-28420: 1 source package rows (vim); 326 state rows across 7 repos (3.19-main, 3.20-main, 3.21-main, 3.22-main, 3.23-main, edge-community, edge-main); fixed 2, open 324. https://security.alpinelinux.org/vuln/CVE-2026-28420
debian not yet assigned CVE-2026-28420 not yet assigned priority: Debian including 1 source packages (vim), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): open 3, resolved 2. https://security-tracker.debian.org/tracker/CVE-2026-28420
redhat medium https://access.redhat.com/security/cve/CVE-2026-28420
suse low https://www.suse.com/security/cve/CVE-2026-28420/
ubuntu medium CVE-2026-28420 medium priority: Ubuntu including 1 source packages (vim), 8 status rows across 8 suites (bionic, focal, jammy, noble, questing, trusty, upstream, xenial): released 8. https://ubuntu.com/security/CVE-2026-28420

Affected software / configurations for CVE-2026-28420

Vendor Product Version Raw CPE
vim vim < 9.2.0076 cpe:2.3:a:vim:vim:*:*:*:*:*:*:*:*

References for CVE-2026-28420

cvelogic Threat Intelligence