CVE-2026-3988 | Inefficient Algorithmic Complexity in GitLab

GitLab has remediated an issue in GitLab CE/EE affecting all versions from 18.5 before 18.8.7, 18.9 before 18.9.3, and 18.10 before 18.10.1 that could have allowed an unauthenticated user to cause a denial of service by making the GitLab instance unresponsive due to improper input validation in GraphQL request processing.

Published: 2026-03-25 Last update: 2026-03-26 Assigner: [email protected] Source: [email protected]
NVD Status：Analyzed，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2026-3988 is rated Moderate Risk (45.8/100): CVSS High severity, with low exploitation likelihood (EPSS 0.22%). Review affected assets and schedule remediation.

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-2026-3988

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 2026-05-03 0.06% 0.22% +0.17%
2 2026-03-31 0.04% 0.06% +0.02%
3 2026-03-26 — 0.04% —

Full EPSS history (3 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-3988

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.5 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
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:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
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:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 3.9 3.6 [email protected]

Weakness enumeration for CVE-2026-3988

OS Trackers for CVE-2026-3988

vendor priority summary link
debian unimportant CVE-2026-3988 unimportant priority: Debian including 1 source packages (gitlab), 1 status rows across 1 suites (sid): resolved 1. https://security-tracker.debian.org/tracker/CVE-2026-3988

Affected software / configurations for CVE-2026-3988

Vendor Product Version Raw CPE
gitlab gitlab >= 18.5.0, < 18.8.7 cpe:2.3:a:gitlab:gitlab:*:*:*:*:community:*:*:*
gitlab gitlab >= 18.5.0, < 18.8.7 cpe:2.3:a:gitlab:gitlab:*:*:*:*:enterprise:*:*:*
gitlab gitlab >= 18.9.0, < 18.9.3 cpe:2.3:a:gitlab:gitlab:*:*:*:*:community:*:*:*
gitlab gitlab >= 18.9.0, < 18.9.3 cpe:2.3:a:gitlab:gitlab:*:*:*:*:enterprise:*:*:*
gitlab gitlab 18.10.0 cpe:2.3:a:gitlab:gitlab:18.10.0:*:*:*:community:*:*:*
gitlab gitlab 18.10.0 cpe:2.3:a:gitlab:gitlab:18.10.0:*:*:*:enterprise:*:*:*

References for CVE-2026-3988

cvelogic Threat Intelligence