Medium severity · published Aug 28, 2026
CVE-2026-81341
wolfEngine reuses the AES-CCM nonce on TLS 1.2 / DTLS 1.2 records
6.5
CVSS
0.3%
EPSS
No
On KEV
Description
wolfEngine before 1.4.1 sources the explicit AES-CCM nonce for TLS 1.2 and DTLS 1.2 records from the record input buffer instead of the TLS sequence number carried in the additional authenticated data. Because the record layer leaves the explicit-nonce field for the cipher to populate, the value read is constant across records, so every AES-CCM record within a connection is encrypted under an identical key and nonce pair. Reusing a CCM key and nonce weakens confidentiality (identical keystream across records, so a known record recovers the others) and integrity (authentication tag forgery). Only wolfEngine is affected; wolfProvider is not. AES-GCM under wolfEngine is tracked separately. AES-CCM cipher suites are not enabled by default and must be explicitly selected, which limits exposure. TLS 1.3 and non-TLS use of the cipher are not affected.
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:N
Attack vector
Network
Complexity
High
Privileges
None
User interaction
None
Confidentiality
High
Integrity
Low
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 25% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
WO
wolfEngine · wolfSSL Inc.
through 1.4.0 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-81341
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-81341
Vendor Advisory
https://www.wolfssl.com/docs/security-vulnerabilities/
More from wolfEngine
7.4
CVE-2026-81020
wolfEngine reuses the AES-GCM nonce on every TLS 1.2 / DTLS 1.2 record
