CVE-2026-87719 Deserialization of Untrusted Data in GitLab

Critical 9.9 Published 12 Sep 2026 Updated 23 Sep 2026

Authenticated users with Duo Chat access can bypass serialization to read sensitive credentials and instance configurations via crafted GraphQL arguments.

Exploited in the wild: Not known
Login needed: Any signed-in user
Attackable: Over the internet
Victim action needed: Not needed
Fix: Available

What is CVE-2026-87719?

CVE-2026-87719 is a critical unsafe deserialization vulnerability in Gitlab Gitlab, published on 12 Sep 2026. Any signed-in user can exploit it over the network, with no action from the victim.

Official description

GitLab has remediated an issue in GitLab EE affecting all versions from 18.3 before 18.11.12, 19.0 before 19.0.9, 19.1 before 19.1.8, 19.2 before 19.2.6, and 19.3 before 19.3.2 that under certain conditions could allow an authenticated user with Duo Chat access to obtain Advanced Search instance configurations and sensitive credentials using a specially crafted GraphQL subscription argument to bypass serialization and perform server object lookup.

Weakness: CWE-502

Which versions are affected by CVE-2026-87719?

1 open source package ship an affected version, including gitlab. It affects 1 product.

Package	Affected	Fixed in
`gitlab` Bitnami	From `18.3.0`	`19.1.8, 19.2.6, 19.3.2`

Products include Gitlab Gitlab.

How do I fix CVE-2026-87719?

Upgrade gitlab to a fixed version for your release line: 19.1.8, 19.2.6 or 19.3.2.

Upgrade, and only deserialise data from trusted sources or with an allow-list of types. More about Unsafe deserialization.

Is CVE-2026-87719 being exploited?

There is no known exploitation of CVE-2026-87719 in the wild and no public exploit code.

All Gitlab Gitlab vulnerabilities

Sources

Also known as BIT-gitlab-2026-87719, GHSA-prp4-5w2g-8v2c, MINI-6489-2h8p-3xp9, MINI-7c26-m7p6-9w6x, MINI-px6q-vhwf-4v3g.