CVE-2026-3857
Published: 25 March 2026
Summary
CVE-2026-3857 is a high-severity CSRF (CWE-352) vulnerability in Gitlab Gitlab. Its CVSS base score is 8.1 (High).
Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked at the 1.7th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.
The strongest mitigations our analysis identified are NIST 800-53 SC-23 (Session Authenticity) and SI-10 (Information Input Validation).
Threat & Defense at a Glance
Threat & Defense Details
Mitigating Controls (NIST 800-53 r5)AI
SC-23 mandates protections for the authenticity of communications sessions, directly preventing CSRF attacks that allow forged GraphQL mutations on behalf of authenticated users.
SI-10 requires validation of all information inputs, including CSRF tokens, to block unauthorized execution of arbitrary GraphQL mutations.
SI-2 ensures timely identification, reporting, and correction of flaws like insufficient CSRF protection through patching to remediated GitLab versions.
MITRE ATT&CK Enterprise TechniquesAI
Why these techniques?
CSRF in public-facing GitLab web app (T1190) is directly exploitable by delivering a malicious link to an authenticated user (T1566.002) to trigger arbitrary GraphQL mutations.
NVD Description
GitLab has remediated an issue in GitLab CE/EE affecting all versions from 17.10 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 execute arbitrary GraphQL mutations on behalf of authenticated users due…
more
to insufficient CSRF protection.
Deeper analysisAI
CVE-2026-3857 is a cross-site request forgery (CSRF) vulnerability, classified under CWE-352, affecting GitLab Community Edition (CE) and Enterprise Edition (EE) in all versions from 17.10 prior to 18.8.7, 18.9 prior to 18.9.3, and 18.10 prior to 18.10.1. The flaw stems from insufficient CSRF protection, enabling unauthenticated users to execute arbitrary GraphQL mutations on behalf of authenticated users. It carries a CVSS v3.1 base score of 8.1 (AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N), indicating high severity due to its network accessibility, low attack complexity, lack of required privileges, and potential for high confidentiality and integrity impacts.
An unauthenticated attacker can exploit this vulnerability by tricking an authenticated GitLab user into performing an action, such as clicking a malicious link or visiting a crafted webpage, which requires user interaction. Upon success, the attacker executes arbitrary GraphQL mutations impersonating the victim user, potentially allowing unauthorized data access, modification of repository settings, or other privileged operations depending on the victim's permissions.
GitLab has remediated the issue through patch releases, including GitLab 18.10.1, as detailed in their release notes. Security practitioners should upgrade affected instances to GitLab 18.8.7, 18.9.3, 18.10.1, or later versions. Additional details are available in GitLab's work item 592828 and the associated HackerOne disclosure report 3584382.
Details
- CWE(s)