GitLab: Authorization Bypass Through User-Controlled Key
CVE-2026-4868 is a high-severity authorization bypass through user-controlled key vulnerability in GitLab, with a CVSS 3.1 base score of 8.2 out of 10. It can be exploited remotely over the network by an attacker with a low-privileged account, without any action from a user. The record lists versions 18.10.7, 18.11.4, 19.0.1 as the first without the flaw, so updating GitLab to one of those releases or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.43% chance of exploitation within 30 days, which is low compared with other CVEs.
High severity with no evidence of exploitation so far.
What to do
- Update GitLab to 18.10.7 or 18.11.4 or 19.0.1, whichever matches your release line, or a later version.
- Read the advisory on about.gitlab.com for workarounds and exact fixed builds.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| GitLab | GitLab | 18.8 up to, but not including, 18.10.7; 18.11 up to, but not including, 18.11.4; 19.0 up to, but not including, 19.0.1 | 18.10.7, 18.11.4, 19.0.1 |
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- NetworkCan be exploited remotely over a network, including the internet.
- Attack complexity
- HighSuccess depends on conditions outside the attacker's control.
- Privileges required
- LowA basic user account is enough.
- User interaction
- NoneNo action by a victim is required.
- Scope
- ChangedThe attack can reach beyond the vulnerable component into other systems.
- Confidentiality
- HighAll data handled by the component can be read.
- Integrity
- HighData or code can be modified at will.
- Availability
- NoneAvailability is not affected.
Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:N. Scored by CNA (gitlab.com).
Official description
GitLab has remediated an issue in GitLab EE affecting all versions from 18.8 before 18.10.7, 18.11 before 18.11.4, and 19.0 before 19.0.1 that, under certain conditions, could have allowed an authenticated user to cause specific Duo AI workflows to run under another user's identity due to improper user identity resolution when triggering Duo AI workflow runners.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Authorization Bypass Through User-Controlled Key
The system's authorization functionality does not prevent one user from gaining access to another user's data or record by modifying the key value identifying the data.
How developers prevent this class of flaw
- For each and every data access, ensure that the user has sufficient privilege to access the record that is being requested.
- Make sure that the key that is used in the lookup of a specific user's record is not controllable externally by the user or that any tampering can be detected.
- Use encryption in order to make it more difficult to guess other legitimate values of the key or associate a digital signature with the key so that the server can verify that there has been no tampering.
More Authorization Bypass Through User-Controlled Key vulnerabilities (CWE-639)
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
- Record last changed materially (score, affected products, status or references).
References
Advisories
Other references
- hackerone.com/reports/3619872Permissions Required
Other vulnerabilities in GitLab
- 7.1 High severity
- 8.2 High severity
- 7.5 High severity
- 10.0 Critical severity
- 10.0 Critical severity
- 7.3 High severity
Recent Authorization Bypass Through User-Controlled Key vulnerabilities
- 7.5 High severity
- 8.2 High severity
- 8.8 High severity
- 7.1 High severity
- 7.5 High severity
- 7.5 High severity
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