CVE-2026-3988
Denial of Service in GitLab GraphQL via Input Validation Flaw
Publication date: 2026-03-25
Last updated on: 2026-03-26
Assigner: GitLab Inc.
Description
Description
CVSS Scores
EPSS Scores
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Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| gitlab | gitlab | From 18.9.0 (inc) to 18.9.3 (exc) |
| gitlab | gitlab | 18.10.0 |
| gitlab | gitlab | From 18.5.0 (inc) to 18.8.7 (exc) |
| gitlab | gitlab | From 18.9.0 (inc) to 18.9.3 (exc) |
| gitlab | gitlab | From 18.5.0 (inc) to 18.8.7 (exc) |
| gitlab | gitlab | 18.10.0 |
Helpful Resources
Exploitability
| CWE ID | Description |
|---|---|
| CWE-407 | An algorithm in a product has an inefficient worst-case computational complexity that may be detrimental to system performance and can be triggered by an attacker, typically using crafted manipulations that ensure that the worst case is being reached. |
Attack-Flow Graph
AI Powered Q&A
Can you explain this vulnerability to me?
This vulnerability in GitLab CE/EE affects versions from 18.5 before 18.8.7, 18.9 before 18.9.3, and 18.10 before 18.10.1. It allows an unauthenticated user to cause a denial of service by making the GitLab instance unresponsive. The issue arises due to improper input validation in the processing of GraphQL requests.
How can this vulnerability impact me? :
The impact of this vulnerability is a denial of service (DoS) condition. An attacker who is not authenticated can exploit this flaw to make the GitLab instance unresponsive, potentially disrupting access to the service and affecting availability.
What immediate steps should I take to mitigate this vulnerability?
To mitigate this vulnerability, you should upgrade your GitLab instance to a fixed version. Specifically, update to GitLab CE/EE versions 18.8.7 or later, 18.9.3 or later, or 18.10.1 or later, as these versions contain the remediation for the denial of service issue caused by improper input validation in GraphQL request processing.