CVE-2026-87719 PUBLISHED

Deserialization of Untrusted Data in GitLab

Assigner: GitLab
Reserved: 09.09.2026 Published: 12.09.2026 Updated: 12.09.2026

GitLab has remediated an issue in GitLab EE affecting all versions from 18.3 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.

Metrics

CVSS 3.1

CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
CVSS Score: 9.9

Attack Vector	Network	Scope	Changed
Attack Complexity	Low	Confidentiality Impact	High
Privileges Required	Low	Integrity Impact	High
User Interaction	None	Availability Impact	High

CVSS 3.1

Product Status

Vendor	GitLab
Product	GitLab
Versions	Default: unaffected affected from 18.3 to 19.1.8 (excl.) affected from 19.2 to 19.2.6 (excl.) affected from 19.3 to 19.3.2 (excl.)

Solutions

Upgrade to versions 19.1.8, 19.2.6, 19.3.2 or above.

Credits

Thanks [kyyblin](https://hackerone.com/kyyblin) for reporting this vulnerability through our HackerOne bug bounty program finder

References

Problem Types

CWE-502: Deserialization of Untrusted Data CWE