Unauthorized data access via insufficient SAML username checks
Published May 29, 2026 · Updated May 29, 2026
Incorrect authorization in JetBrains TeamCity On-Premises before 2026.1 allows remote attackers to read or alter data through SAML. The SAML plugin accepts a username without sufficient validation during authentication; JetBrains has not disclosed the accepted input or failed comparison. Exploitation requires network access to a server with the HTTP SAML 2.0 module enabled; reported impact is limited to unauthorized data reading and modification.
Summary
What happened
Incorrect authorization in JetBrains TeamCity On-Premises before 2026.1 allows remote attackers to read or alter data through SAML. The SAML plugin accepts a username without sufficient validation during authentication; JetBrains has not disclosed the accepted input or failed comparison. Exploitation requires network access to a server with the HTTP SAML 2.0 module enabled; reported impact is limited to unauthorized data reading and modification.
The record
- CVE
- CVE-2026-49376
- Published
- May 29, 2026
- Updated
- May 29, 2026
- Vendor
- JetBrains
- Product
- TeamCity On-Premises
- Classifications
- CWE-863, T1190
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- May 29, 2026CVE publishedPublication date reported by the CVE source.
- May 29, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
Compare your product and version with the public record. A matching version still requires validation against your environment.
Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=0 <2026.1
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Public exploit references
No public exploit references are available in this record.
Labels summarize the accepted research assessment. They do not indicate a test against your environment.
Technologies
Your stack
See the directory against your own environment.
Your stack
Check the software in your environment
Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.
Book a demo