Unauthenticated user impersonation via inverted signature check
Published Aug 25, 2026 · Updated Aug 26, 2026
Improper authentication in Apache Hive 4.0.0 through 4.2.0 allows remote attackers to impersonate any Hive user via a forged bearer token. HiveSamlAuthTokenGenerator.signatureMatches reverses MessageDigest.isEqual, accepting a mismatched signature while rejecting the matching signature. The flaw is reachable only when HiveServer2 uses HTTP transport with native SAML authentication, where access to /cliservice yields an authenticated session without Hive credentials or an IdP login.
Summary
What happened
Improper authentication in Apache Hive 4.0.0 through 4.2.0 allows remote attackers to impersonate any Hive user via a forged bearer token. HiveSamlAuthTokenGenerator.signatureMatches reverses MessageDigest.isEqual, accepting a mismatched signature while rejecting the matching signature. The flaw is reachable only when HiveServer2 uses HTTP transport with native SAML authentication, where access to /cliservice yields an authenticated session without Hive credentials or an IdP login.
The record
- CVE
- CVE-2026-53561
- Published
- Aug 25, 2026
- Updated
- Aug 26, 2026
- Vendor
- The Apache Software Foundation
- Product
- Apache Hive
- Classifications
- CWE-345, CWE-305, CWE-287, T1190
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Aug 25, 2026CVE publishedPublication date reported by the CVE source.
- Aug 26, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=4.0.0 <=4.2.0
What conditions does exploitation require?
What is affected?
Published CVSS scores
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Attacks
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Public exploit references
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Technologies
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Your stack
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