Role token forgery via timing-leaky signature comparison
Published Feb 7, 2024 · Updated Aug 2, 2024
Observable timing discrepancy in affected Apache Pulsar releases allows remote attackers to forge SASL role tokens that pass verification. SaslRoleTokenSigner.verifyAndExtract compares an attacker-supplied Base64 signature with the computed SHA-512 string using String.equals, whose early exit leaks matching-prefix information through response timing. The SASL Authentication Provider must be configured and network-reachable; a forged token receives the authorization assigned to its asserted role, with no reported availability impact.
Summary
What happened
Observable timing discrepancy in affected Apache Pulsar releases allows remote attackers to forge SASL role tokens that pass verification. SaslRoleTokenSigner.verifyAndExtract compares an attacker-supplied Base64 signature with the computed SHA-512 string using String.equals, whose early exit leaks matching-prefix information through response timing. The SASL Authentication Provider must be configured and network-reachable; a forged token receives the authorization assigned to its asserted role, with no reported availability impact.
The record
- CVE
- CVE-2023-51437
- Published
- Feb 7, 2024
- Updated
- Aug 2, 2024
- Vendor
- The Apache Software Foundation
- Product
- Apache Pulsar
- Classifications
- CWE-203, T1550
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Feb 7, 2024CVE publishedPublication date reported by the CVE source.
- Aug 2, 2024Record 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=0 <=2.10.5
- Affected versionversion=2.11.0 <=2.11.2
- Affected versionversion=3.0.0 <=3.0.1
- Affected versionversion=3.1.0
What conditions does exploitation require?
What is affected?
Published CVSS scores
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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.
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Technologies
Your stack
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Your stack
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