Session-key disclosure via variable-time RSA padding removal
Published Dec 5, 2023 · Updated Feb 13, 2025
Timing side channel in Go standard library crypto/tls before 1.20.0 allows remote attackers to recover TLS session-key bits. RSA-based TLS key exchange removes PKCS#1 padding with math/big operations whose execution time varies with attacker-controlled ciphertext. Exploitation requires repeated timing observations against a service that negotiates RSA key exchange, and the reported impact is disclosure of session-key material without integrity or availability loss.
Summary
What happened
Timing side channel in Go standard library crypto/tls before 1.20.0 allows remote attackers to recover TLS session-key bits. RSA-based TLS key exchange removes PKCS#1 padding with math/big operations whose execution time varies with attacker-controlled ciphertext. Exploitation requires repeated timing observations against a service that negotiates RSA key exchange, and the reported impact is disclosure of session-key material without integrity or availability loss.
The record
- CVE
- CVE-2023-45287
- Published
- Dec 5, 2023
- Updated
- Feb 13, 2025
- Vendor
- Go standard library
- Product
- crypto/tls
- Classifications
- CWE-203
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Dec 5, 2023CVE publishedPublication date reported by the CVE source.
- Feb 13, 2025Record 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 <1.20.0
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
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Weakness, pattern, technique
Public exploit references
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Technologies
Your stack
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Your stack
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