What is CVE-2026-1403?

CVE-2026-1403 is a medium-severity vulnerability in GitLab, classified under Allocation of Resources Without Limits or Throttling. CVSS score: 6.5/10. Published 2026-10-07.

How severe is CVE-2026-1403?

Medium severity. CVSS v3 base score is 6.5 out of 10.

Resource exhaustion in GitLab

CVE-2026-1403

GitLab has remediated an issue in GitLab CE/EE affecting all versions from 11.7 before 18.8.9, 18.9 before 18.9.5, and 18.10 before 18.10.3 that when importing CSV files could have allowed an authenticated user to cause denial of service to Sidekiq workers due to improper validation of CSV file structure.

Published 2026-10-07.

CVSS v3 metric

CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H.

EPSS exploit prediction

No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.

Affected products

GitLab

Weakness classification (CWE)

CWE-770 — Allocation of Resources Without Limits or Throttling

References

hackerone.com/reports/3328937 (technical-description, permissions-required, exploit)
gitlab.com/gitlab-org/gitlab/-/work_items/587573

Frequently asked questions

What is CVE-2026-1403?: CVE-2026-1403 is a medium-severity vulnerability in GitLab, classified under Allocation of Resources Without Limits or Throttling. CVSS score: 6.5/10. Published 2026-10-07.
How severe is CVE-2026-1403?: Medium severity. CVSS v3 base score is 6.5 out of 10.