How severe is CVE-2026-28421?

CVE-2026-28421 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over local access with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity low, and availability low.

Is CVE-2026-28421 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (7th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-28421?

CVE-2026-28421 affects Vim. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-28421?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2026-28421 have an EU (EUVD) identifier?

Yes. CVE-2026-28421 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-9089.

When was CVE-2026-28421 published?

CVE-2026-28421 was published on 2026-02-27 and last updated on 2026-06-17.

CVE-2026-28421

CVE-2026-28421 is a medium-severity vulnerability in Vim with a CVSS 3.x base score of 5.3. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-20.

Key facts

Severity: Medium (CVSS 3.x base score 5.3)
EPSS exploit prediction: 0% (7th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-9089
Weakness: CWE-20
Affected product: Vim
Published: 2026-02-27
Last modified: 2026-06-17

Description

Vim is an open source, command line text editor. Versions prior to 9.2.0077 have a heap-buffer-overflow and a segmentation fault (SEGV) exist in Vim's swap file recovery logic. Both are caused by unvalidated fields read from crafted pointer blocks within a swap file. Version 9.2.0077 fixes the issue.

Frequently asked questions

What is CVE-2026-28421?: Vim is an open source, command line text editor. Versions prior to 9.2.0077 have a heap-buffer-overflow and a segmentation fault (SEGV) exist in Vim's swap file recovery logic. Both are caused by unvalidated fields read from crafted pointer blocks within a swap file. Version 9.2.0077 fixes the issue.
How severe is CVE-2026-28421?: CVE-2026-28421 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over local access with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity low, and availability low.
Is CVE-2026-28421 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (7th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-28421?: CVE-2026-28421 affects Vim. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-28421?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-28421 have an EU (EUVD) identifier?: Yes. CVE-2026-28421 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-9089.
When was CVE-2026-28421 published?: CVE-2026-28421 was published on 2026-02-27 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:vim:vim:*:*:*:*:*:*:*:*

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