TLS plaintext recovery and forgery via nonce reuse
Published Aug 28, 2026 · Updated Aug 28, 2026
Cryptographic nonce reuse in wolfSSL wolfProvider 1.0.0 through 1.2.1 allows remote attackers to read and forge TLS records. The TLS write-key setup generates one 8-byte explicit AES-GCM nonce, and the encryption context never increments it before encrypting later records. Exploitation requires multiple TLS 1.2 or DTLS 1.2 AES-GCM records under one key plus known plaintext; it reveals other record plaintext and enables authentication-tag forgery, but does not affect AES-CCM, TLS 1.3, or non-TLS cipher use.
Summary
What happened
Cryptographic nonce reuse in wolfSSL wolfProvider 1.0.0 through 1.2.1 allows remote attackers to read and forge TLS records. The TLS write-key setup generates one 8-byte explicit AES-GCM nonce, and the encryption context never increments it before encrypting later records. Exploitation requires multiple TLS 1.2 or DTLS 1.2 AES-GCM records under one key plus known plaintext; it reveals other record plaintext and enables authentication-tag forgery, but does not affect AES-CCM, TLS 1.3, or non-TLS cipher use.
The record
- CVE
- CVE-2026-81019
- Published
- Aug 28, 2026
- Updated
- Aug 28, 2026
- Vendor
- wolfSSL
- Product
- wolfProvider
- Classifications
- CWE-323, T1040
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Aug 28, 2026CVE publishedPublication date reported by the CVE source.
- Aug 28, 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?
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- Affected versionversion=0 <=1.2.1
What conditions does exploitation require?
What is affected?
Published CVSS scores
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Attacks
What attackers are doing with it
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Public exploit references
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Technologies
Your stack
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Your stack
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