6.5

CVE-2026-81341: wolfEngine reuses the AES-CCM nonce on TLS 1.2 / DTLS 1.2 records

Analyzed
Published 28-08-2026Last modified 28-08-2026

Vulnerability summary

CVE-2026-81341 is a medium (CVSS 6.5) Reusing a Nonce, Key Pair in Encryption vulnerability in wolfssl inc. wolfengine. EPSS estimates a 0.32% chance of exploitation in the next 30 days, higher than 24.8% of scored vulnerabilities.

Priority
Routine

Not severe (CVSS 6.5, network access); no exploitation reported by the 5 checked sources

Source freshness unavailable

How is this decided?
CVSS score
6.5/10
010
Medium · v3.1 (CVE.org)
EPSS score
0.32%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedNot listed by any tracked catalog.
RansomwareNot flaggedNo ransomware use recorded.
Public exploits0No public exploits recorded

Timeline

  1. 28-08-2026
    PublishedVulnerability first disclosed.
  2. 28-08-2026
    Last modifiedVulnerability information updated.

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 metrics

2 scores · 2 sources · 1 version

EPSS trend

Probability

0.32%

Chance of exploitation in the next 30 days

Percentile

25%

Versus all other CVEs

30-day change

No change 0.00 pp

From 0.32% on 04-10-2026

04-10-202603-11-2026

Known exploited

Compare KEV catalogs
CISA KEV

Not in the CISA KEV catalog.

ENISA CNW

Not in the ENISA CNW catalog.

CIRCL

Not in the CIRCL catalog.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Version check

Known conditions: network-reachable, no authentication, no user interaction (CVSS vector). Other conditions: not stated in public data.

Wolfssl1 product
Wolfssl inc.1 product

2 vendors · 2 products

References

1 links