TLS cipher downgrade via incomplete ServerHello parsing
Published Aug 27, 2024 · Updated Aug 27, 2024
Cryptographic downgrade in wolfSSL 5.7.0 and earlier allows remote attackers to establish TLS using an unoffered cipher suite. The TLS 1.3 client downgrade path in src/tls13.c parses extensions but skips full ServerHello validation, accepting the server-selected suite. Exploitation requires a downgrade-capable client to connect to a malicious TLS 1.2 server; the resulting session uses a suite outside the client's offer.
Summary
What happened
Cryptographic downgrade in wolfSSL 5.7.0 and earlier allows remote attackers to establish TLS using an unoffered cipher suite. The TLS 1.3 client downgrade path in src/tls13.c parses extensions but skips full ServerHello validation, accepting the server-selected suite. Exploitation requires a downgrade-capable client to connect to a malicious TLS 1.2 server; the resulting session uses a suite outside the client's offer.
The record
- CVE
- CVE-2024-5814
- Published
- Aug 27, 2024
- Updated
- Aug 27, 2024
- Vendor
- wolfSSL
- Product
- wolfSSL
- Classifications
- CWE-284
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Aug 27, 2024CVE publishedPublication date reported by the CVE source.
- Aug 27, 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 <=5.70
- Affected versionversion=0 <=5.7.0
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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