Goal Reached Thanks to every supporter — we hit 100%!

Goal: 1000 CNY · Raised: 1359 CNY

100%
Buy Us a Coffee

CVE-2026-3254— Improper Restriction of Rendered UI Layers or Frames in GitLab

Quick assessment

Affected
GitLab GitLab
Exploitation
No confirmed in-the-wild exploitation; assess based on exposure
Recommended action
Check the vendor advisory and references for a fixed version. If immediate upgrade is impossible, restrict exposure and increase monitoring.

GitLab Enterprise Edition（EE）和GitLab Community Edition（CE）都是美国GitLab公司的产品。GitLab Enterprise Edition是一套内容管理系统。GitLab Community Edition是一种社区版 GitLab 。 GitLab CE/EE 18.11.1之前版本存在安全漏洞，该漏洞源于Mermaid沙箱输入验证不当，可能导致认证用户将未经授权的内容加载到其他用户浏览器。

CVSS 3.5 · Low EPSS 0.26% · P16

Possible ATT&CK Techniques 1 AI

T1190 · Exploit Public-Facing Application
Get alerts for future matching vulnerabilities Log in to subscribe

I. Basic Information for CVE-2026-3254

Vulnerability Information
Have questions about the vulnerability? See if Shenlong's analysis helps!
View Shenlong Deep Dive ↗

Although we use advanced large model technology, its output may still contain inaccurate or outdated information.Shenlong tries to ensure data accuracy, but please verify and judge based on the actual situation.

Vulnerability Title
Improper Restriction of Rendered UI Layers or Frames in GitLab
Source: CVE Program / CVE List V5
Vulnerability Description
GitLab has remediated an issue in GitLab CE/EE affecting all versions from 18.11 before 18.11.1 that under certain conditions could have allowed an authenticated user to load unauthorized content into another user's browser due to improper input validation in the Mermaid sandbox.
Source: CVE Program / CVE List V5
CVSS Information
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:L/A:N
Source: CVE Program / CVE List V5
Vulnerability Type
不当限制渲染UI层或帧
Source: CVE Program / CVE List V5
Vulnerability Title
GitLab CE/EE 安全漏洞
Source: CNNVD (China National Vulnerability Database)
Vulnerability Description
GitLab Enterprise Edition（EE）和GitLab Community Edition（CE）都是美国GitLab公司的产品。GitLab Enterprise Edition是一套内容管理系统。GitLab Community Edition是一种社区版 GitLab 。 GitLab CE/EE 18.11.1之前版本存在安全漏洞，该漏洞源于Mermaid沙箱输入验证不当，可能导致认证用户将未经授权的内容加载到其他用户浏览器。
Source: CNNVD (China National Vulnerability Database)
CVSS Information
N/A
Source: CNNVD (China National Vulnerability Database)
Vulnerability Type
N/A
Source: CNNVD (China National Vulnerability Database)

Affected Products

Vendor Product Affected Versions CPE Subscribe
GitLab GitLab 18.11 ~ 18.11.1 cpe:2.3:a:gitlab:gitlab:*:*:*:*:*:*:*:*

II. Public POCs for CVE-2026-3254

# POC Description Source Link Shenlong Link
AI-Generated POC Premium

No public POC found.

Login to generate AI POC

III. Intelligence Information for CVE-2026-3254

请登录查看更多情报信息。

Same Patch Batch · GitLab · 2026-04-22 · 11 CVEs total

CVE-2026-4922 8.1 HIGH Cross-Site Request Forgery (CSRF) in GitLab
CVE-2026-5262 8.0 HIGH Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') in Gi
CVE-2026-5816 8.0 HIGH Improper Resolution of Path Equivalence in GitLab
CVE-2025-0186 6.5 MEDIUM Allocation of Resources Without Limits or Throttling in GitLab
CVE-2025-3922 6.5 MEDIUM Allocation of Resources Without Limits or Throttling in GitLab
CVE-2025-6016 6.5 MEDIUM Allocation of Resources Without Limits or Throttling in GitLab
CVE-2026-1660 6.5 MEDIUM Allocation of Resources Without Limits or Throttling in GitLab
CVE-2026-6515 5.4 MEDIUM Insufficient Session Expiration in GitLab
CVE-2026-5377 4.3 MEDIUM Incorrect Authorization in GitLab
CVE-2025-9957 2.7 LOW Incorrect Authorization in GitLab

IV. Related Vulnerabilities

Same product: GitLab
Same vendor: GitLab
Same weakness: CWE-1021

V. Comments for CVE-2026-3254

No comments yet

Leave a comment