Ce mail provient de l'extérieur, restons vigilants

=====================================================================

                            CERT-Renater

                Note d'Information No. 2026/VULN412
_____________________________________________________________________

DATE                : 22/04/2026

HARDWARE PLATFORM(S): /

OPERATING SYSTEM(S): Systems running GitLab versions prior to 18.11.1,
                                    18.10.4, 18.9.6.

=====================================================================
https://docs.gitlab.com/releases/patches/patch-release-gitlab-18-11-1-released/
_____________________________________________________________________

GitLab Patch Release: 18.11.1, 18.10.4, 18.9.6

On April 22, 2026, we released versions 18.11.1, 18.10.4, 18.9.6 for
GitLab Community Edition (CE) and Enterprise Edition (EE).

These versions contain important bug and security fixes, and we
strongly recommend that all self-managed GitLab installations be
upgraded to one of these versions immediately. GitLab.com is already
running the patched version. GitLab Dedicated customers do not need
to take action.

GitLab releases fixes for vulnerabilities in patch releases. There are
two types of patch releases: scheduled releases and ad-hoc critical
patches for high-severity vulnerabilities. Scheduled releases are
released twice a month on the second and fourth Wednesdays. For more
information, please visit our releases handbook and security FAQ. You
can see all of GitLab release blog posts here.

For security fixes, the issues detailing each vulnerability are made
public on our issue tracker 30 days after the release in which they
were patched.

We are committed to ensuring that all aspects of GitLab that are
exposed to customers or that host customer data are held to the
highest security standards. To maintain good security hygiene, it
is highly recommended that all customers upgrade to the latest
patch release for their supported version. You can read more best
practices in securing your GitLab instance in our blog post.


Recommended Action

We strongly recommend that all installations running a version
affected by the issues described below are upgraded to the latest
version as soon as possible.

When no specific deployment type (omnibus, source code, helm chart,
etc.) of a product is mentioned, it means all types are affected.


Security fixes

Table of security fixes

Title	Severity
Cross-Site Request Forgery issue in GraphQL API impacts GitLab CE/EE
High

Improper Resolution of Path Equivalence issue in Web IDE asset
impacts GitLab CE/EE	High

Cross-site Scripting issue in Storybook impacts GitLab CE/EE
High

Denial of Service issue in discussions endpoint impacts GitLab CE/EE
Medium

Denial of Service issue in Jira import impacts GitLab CE/EE	Medium

Denial of Service issue in notes endpoint impacts GitLab CE/EE	Medium

Denial of Service issue in GraphQL API impacts GitLab CE/EE	Medium

Insufficient Session Expiration issue in virtual registry credentials
validation impacts GitLab CE/EE	Medium

Improper Access Control issue in issue description renderer impacts
GitLab CE/EE	Medium

Improper Restriction of Rendered UI Layers or Frames issue in Mermaid
sandbox impacts GitLab CE/EE	Low

Improper Access Control issue in project fork relationship API impacts
GitLab CE/EE	Low


CVE-2026-4922 - Cross-Site Request Forgery issue in GraphQL API impacts
GitLab CE/EE

GitLab has remediated an issue that could have allowed an
unauthenticated user to execute GraphQL mutations on behalf of
authenticated users due to insufficient CSRF protection.

Impacted Versions: GitLab CE/EE: all versions from 17.0 before
18.9.6, 18.10 before 18.10.4, and 18.11 before 18.11.1
CVSS 8.1 (CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N)

Thanks ahacker1 for reporting this vulnerability through our
HackerOne bug bounty program


CVE-2026-5816 - Improper Resolution of Path Equivalence issue
in Web IDE asset impacts GitLab CE/EE

GitLab has remediated an issue that could have allowed an
unauthenticated user to execute arbitrary JavaScript in a
user’s browser session due to improper path validation
under certain conditions.

Impacted Versions: GitLab CE/EE: all versions from 18.10
before 18.10.4 and 18.11 before 18.11.1
CVSS 8.0 (CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:H/I:H/A:N)

Thanks joaxcar for reporting this vulnerability through
our HackerOne bug bounty program


CVE-2026-5262 - Cross-site Scripting issue in Storybook
impacts GitLab CE/EE

GitLab has remediated an issue that under certain conditions
could have allowed an unauthenticated user to access
tokens in the Storybook development environment due to
improper input validation.

Impacted Versions: GitLab CE/EE: all versions from 16.1
before 18.9.6, 18.10 before 18.10.4, and 18.11 before
18.11.1
CVSS 8.0 (CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:H/I:H/A:N)

Thanks joaxcar for reporting this vulnerability through
our HackerOne bug bounty program


CVE-2025-0186 - Denial of Service issue in discussions
endpoint impacts GitLab CE/EE

GitLab has remediated an issue that could have allowed
an authenticated user to cause denial of service under
certain conditions by exhausting server resources by
making crafted requests to a discussions endpoint.

Impacted Versions: GitLab CE/EE: all versions from 10.6
before 18.9.6, 18.10 before 18.10.4, and 18.11 before
18.11.1
CVSS 6.5 (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H)

Thanks pwnie for reporting this vulnerability through
our HackerOne bug bounty program


CVE-2026-1660 - Denial of Service issue in Jira import
impacts GitLab CE/EE

GitLab has remediated an issue that under certain
conditions could have allowed an authenticated user to
cause denial of service when importing issues due to
improper input validation.

Impacted Versions: GitLab CE/EE: all versions from 12.3
before 18.9.6, 18.10 before 18.10.4, and 18.11 before
18.11.1
CVSS 6.5 (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H)

Thanks a92847865 for reporting this vulnerability through
our HackerOne bug bounty program


CVE-2025-6016 - Denial of Service issue in notes endpoint
impacts GitLab CE/EE

GitLab has remediated an issue that could have allowed an
authenticated user to cause denial of service due to
insufficient resource allocation limits when retrieving
notes under certain conditions.

Impacted Versions: GitLab CE/EE: all versions from 9.2
before 18.9.6, 18.10 before 18.10.4, and 18.11 before
18.11.1
CVSS 6.5 (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H)

Thanks pwnie for reporting this vulnerability through our
HackerOne bug bounty program


CVE-2025-3922 - Denial of Service issue in GraphQL API
impacts GitLab CE/EE

GitLab has remediated an issue that could have allowed an
authenticated user to cause denial of service by
overwhelming system resources under certain conditions
due to insufficient resource allocation limits in the
GraphQL API.

Impacted Versions: GitLab CE/EE: all versions from 12.4
before 18.9.6, 18.10 before 18.10.4, and 18.11 before
18.11.1
CVSS 6.5 (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H)

Thanks pwnie for reporting this vulnerability through our
HackerOne bug bounty program


CVE-2026-6515 - Insufficient Session Expiration issue in
virtual registry credentials validation impacts GitLab CE/EE

GitLab has remediated an issue that could have allowed a
user to use invalidated or incorrectly scoped credentials
to access Virtual Registries under certain conditions.

Impacted Versions: GitLab CE/EE: all versions from 18.2
before 18.9.6, 18.10 before 18.10.4, and 18.11 before
18.11.1
CVSS 5.4 (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N)

This vulnerability has been discovered internally by GitLab
team member David Fernandez


CVE-2026-5377 - Improper Access Control issue in issu
 description renderer impacts GitLab CE/EE

GitLab has remediated an issue that could have allowed an
authenticated user to access titles of confidential or private
issues in public projects due to improper access control in
the issue description rendering process.

Impacted Versions: GitLab CE/EE: all versions from 18.11
before 18.11.1
CVSS 4.3 (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N)

Thanks yvvdwf for reporting this vulnerability through our
HackerOne bug bounty program


CVE-2026-3254 - Improper Restriction of Rendered UI Layers
or Frames issue in Mermaid sandbox impacts GitLab CE/EE

GitLab has remediated an issue 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.

Impacted Versions: GitLab CE/EE: all versions from 18.11
before 18.11.1
CVSS 3.5 (CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:L/A:N)

Thanks joaxcar for reporting this vulnerability through our
HackerOne bug bounty program


CVE-2025-9957 - Improper Access Control issue in project
fork relationship API impacts GitLab CE/EE

GitLab has remediated an issue that under certain conditions
could have allowed an authenticated user with project owner
permissions to bypass group fork prevention settings due to
improper authorization checks.

Impacted Versions: GitLab CE/EE: all versions from 11.2 before
18.9.6, 18.10 before 18.10.4, and 18.11 before 18.11.1
CVSS 2.7 (CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:L/A:N)

Thanks theluci for reporting this vulnerability through our
HackerOne bug bounty program


Bug fixes

18.11.1

    Backport- Use force_index_repo task type for Zoekt
schema_version bump reindexing
    Backport docs: Update PostgreSQL version documentation
for PG17
    [18.11] Skip re-creating of constraint when migration
spec is skipped
    Backport of " 18.11 What’s new"
    Revert “Merge branch ‘renovate-ci-templates/auto-build-image-4.x’ into ‘v18.11.0-ee’”
    Backport of “BBM - Skip 3 migrations referencing dropped
tables”
    [18.11] Fix session ID dropdown never appearing during
active agentic chat
    Backport of ‘Fix JSON tables with non-string values’
    18.11 - Cherry-pick !9288 and !9311 - Remove PackageCloud
CI and rename pulp jobs
    Backport of ‘Remove package OS check from deployer task’ - 18.11

18.10.4

    [18.10] Scope start-rails-specs changes rule to MR pipelines
    Backport of ‘Fix runner token reset returning 500 for unassigned
project runners’ to 18.10
    Backport of ‘Fix flaky new_project_spec.rb by scoping within
pane’
    18.10 Backport of ‘Update rack to 2.2.23’
    Backport of “Skip BBMs referencing dropped tables in single-record
bug retry”
    Backport of Added reload to address flaky pipeline spec race
condition
    Backport GITLAB_ZOEKT_INDEXER v1.11.1
    Backport of Fix flaky tests for ui_variable_non_inheritable_when_forward_pipeline_variables_false_spec
    Backport of ‘Skip CI finished builds backfill when ClickHouse
is not configured’
    Backport to 18.10: Geo: Run concurrency limit worker on
secondary sites
    Backport of ‘Geo: Switch blob download to use GitLab::HTTP to
avoid llhttp-ffi issue’
    Backport of Release environment deploy needs Omnibus package
- 18.10
    Backport- Use force_index_repo task type for Zoekt
schema_version bump reindexing
    Backport of add feature flag to gate default Sidekiq
concurrency limit calculation
    [18.10] Skip re-creating of constraint when migration
spec is skipped
    Docs backport: Add note about Agent Platform flow
configurations not available until 18.11
    Backport of praba/release-connections-from-all-hosts
and stomlinson/feature-check-dead-connections to 18.10
    Backport to 18.10: Geo: Fix site validation when outbound
request filtering is enabled
    Ensure postgresql_new is included in GitLab CE
    18.10 backport of ‘Update rack to 2.2.23’
    Upgrade postgresql-17 to 17.8 for 18-10-stable
    Upgrade postgresql-16 to 16.13 for 18-10-stable
    Backport: fix: Set sv timeout when restarting Gitaly to 18.10
    [18.10] Remove Mattermost for SLES-12.5
    18.10 - Cherry-pick !9288 and !9311 - Remove PackageCloud CI
and rename pulp jobs
    Backport of ‘Remove package OS check from deployer task’ - 18.10

18.9.6

    chore: bump gitlab-zoekt to v1.8.2 on 18-9-stable
    [18.9] Scope start-rails-specs changes rule to MR pipelines
    18.9 Backport of ‘update zlib to 3.2.3’
    Backport to 18.9: Geo: Run concurrency limit worker on
secondary sites
    Backport of Release environment deploy needs Omnibus
package - 18.9
    Backport- Use force_index_repo task type for Zoekt
schema_version bump reindexing
    [18.9] Skip re-creating of constraint when migration
spec is skipped
    Docs backport: Add note about Agent Platform flow
configurations not available until 18.11
    Backport of add feature flag to gate default Sidekiq
concurrency limit calculation
    Backport GITLAB_ZOEKT_INDEXER v1.8.2
    Backport to 18.9: Geo: Fix site validation when
outbound request filtering is enabled
    Backport: Ensure postgresql_new is included in GitLab CE
    18.9 backport of ‘Update rack to 2.2.23’
    Upgrade postgresql-17 to 17.8 for 18-9-stable
    Upgrade postgresql-16 to 16.13 for 18-9-stable
    Backport: fix: Set sv timeout when restarting Gitaly to 18.9
    [18.9] Remove Mattermost for SLES-12.5
    18.9 - Cherry-pick !9288 and !9311 - Remove PackageCloud CI
and rename pulp jobs
    Remove .gitlab folder under package gitlab-rails
    Backport of ‘Remove package OS check from deployer
task’ - 18.9


Important notes on upgrading

This patch includes database migrations that may impact
your upgrade process.
Impact on your installation:

    Single-node instances: This patch will cause downtime during
the upgrade as migrations must complete before GitLab can start.
    Multi-node instances: With proper zero-downtime upgrade
procedures, this patch can be applied without downtime.


Regular migrations

The following versions include regular migrations that run
during the upgrade process:

    18.11.1
    18.10.4
    18.9.6

Post-deploy migrations

The following versions include post-deploy migrations that
can run after the upgrade:

    18.11.1
    18.10.4

To learn more about the impact of upgrades on your
installation, see:

    Zero-downtime upgrades for multi-node deployments
    Standard upgrades for single-node installations


Updating

To update GitLab, see the Update page. To update GitLab Runner,
see the Updating the Runner page.
Receive Patch Notifications

To receive patch blog notifications delivered to your inbox,
visit our contact us page. To receive release notifications
via RSS, subscribe to our patch release RSS feed or our
RSS feed for all releases.

=========================================================
+ CERT-RENATER        |    tel : 01-53-94-20-44         +
+ 23/25 Rue Daviel    |    fax : 01-53-94-20-41         +
+ 75013 Paris         |   email:cert@support.renater.fr +
=========================================================




