CVE-2026-5173 | GitLab Community Edition/Enterprise Edition up to 18.8.8/18.9.4/18.10.2 Websocket Connection routine (EUVD-2026-20802)

VDB-356480 · CVE-2026-5173 · EUVD-2026-20802 GITLAB COMMUNITY EDITION/ENTERPRISE EDITION UP TO 18.8.8/18.9.4/18.10.2 WEBSOCKET CONNECTION ROUTINE HISTORYDIFFRELATEJSONXMLCTI CVSS Meta Temp Score Current Exploit Price (≈) CTI Interest Score 7.2 $0-$5k 0.40+ Summaryinfo A vulnerability described as critical has been identified in GitLab Community Edition and Enterprise Edition up to 18.8.8/18.9.4/18.10.2. This vulnerability affects unknown code of the component Websocket Connection Handler. Such manipulation leads to routine. This vulnerability is referenced as CVE-2026-5173. It is possible to launch the attack remotely. No exploit is available. Upgrading the affected component is recommended. Detailsinfo A vulnerability was found in GitLab Community Edition and Enterprise Edition up to 18.8.8/18.9.4/18.10.2. It has been rated as critical. Affected by this issue is an unknown code block of the component Websocket Connection Handler. The manipulation with an unknown input leads to a routine vulnerability. Using CWE to declare the problem leads to CWE-749. The product provides an Applications Programming Interface (API) or similar interface for interaction with external actors, but the interface includes a dangerous method or function that is not properly restricted. Impacted is confidentiality, integrity, and availability. CVE summarizes: GitLab has remediated an issue in GitLab CE/EE affecting all versions from 16.9.6 before 18.8.9, 18.9 before 18.9.5, and 18.10 before 18.10.3 that could have allowed an authenticated user to invoke unintended server-side methods through websocket connections due to improper access control. The advisory is shared for download at gitlab.com. This vulnerability is handled as CVE-2026-5173 since 03/30/2026. The exploitation is known to be easy. The attack may be launched remotely. There are neither technical details nor an exploit publicly available. Upgrading to version 18.8.9, 18.9.5 or 18.10.3 eliminates this vulnerability. The upgrade is hosted for download at about.gitlab.com. The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2026-20802). Productinfo Type Bug Tracking Software Vendor GitLab Name Community Edition Enterprise Edition Version 18.8.0 18.8.1 18.8.2 18.8.3 18.8.4 18.8.5 18.8.6 18.8.7 18.8.8 18.9.0 18.9.1 18.9.2 18.9.3 18.9.4 18.10.0 18.10.1 18.10.2 License open-source Website Vendor: https://gitlab.com/ CPE 2.3info 🔒 🔒 🔒 CPE 2.2info 🔒 🔒 🔒 CVSSv4info VulDB Vector: 🔒 VulDB Reliability: 🔍 CVSSv3info VulDB Meta Base Score: 7.4 VulDB Meta Temp Score: 7.2 VulDB Base Score: 6.3 VulDB Temp Score: 6.0 VulDB Vector: 🔒 VulDB Reliability: 🔍 CNA Base Score: 8.5 CNA Vector (GitLab): 🔒 CVSSv2info Vector Complexity Authentication Confidentiality Integrity Availability Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock VulDB Base Score: 🔒 VulDB Temp Score: 🔒 VulDB Reliability: 🔍 Exploitinginfo Class: Routine CWE: CWE-749 CAPEC: 🔒 ATT&CK: 🔒 Physical: No Local: No Remote: Yes Availability: 🔒 Status: Not defined Price Prediction: 🔍 Current Price Estimation: 🔒 0-Day Unlock Unlock Unlock Unlock Today Unlock Unlock Unlock Unlock Threat Intelligenceinfo Interest: 🔍 Active Actors: 🔍 Active APT Groups: 🔍 Countermeasuresinfo Recommended: Upgrade Status: 🔍 0-Day Time: 🔒 Upgrade: Community Edition/Enterprise Edition 18.8.9/18.9.5/18.10.3 Timelineinfo 03/30/2026 CVE reserved 04/09/2026 +10 days Advisory disclosed 04/09/2026 +0 days VulDB entry created 04/09/2026 +0 days VulDB entry last update Sourcesinfo Vendor: gitlab.com Advisory: gitlab.com Status: Confirmed CVE: CVE-2026-5173 (🔒) GCVE (CVE): GCVE-0-2026-5173 GCVE (VulDB): GCVE-100-356480 EUVD: 🔒 Entryinfo Created: 04/09/2026 02:47 Updated: 04/09/2026 03:24 Changes: 04/09/2026 02:47 (65), 04/09/2026 03:24 (1) Complete: 🔍 Cache ID: 99:FA0:101 Discussion No comments yet. Languages: en. Please log in to comment. ◂ PreviousOverviewNext ▸