Low severity · published Sep 24, 2026
CVE-2026-73064
In Mbed TLS 3.2.0 though 3.6.6 and 4.0.0 through 4.1.0, an attacker who can cause an entropy source to fail can remove or inject bytes into the start of the TLS stream
2.9
CVSS
0.1%
EPSS
No
On KEV
Description
In Mbed TLS 3.2.0 though 3.6.6 and 4.0.0 through 4.1.0, an attacker who can cause an entropy source to fail can remove or inject bytes into the start of the TLS stream. This only affects TLS 1.3 servers.
CVSS vector
CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N
Attack vector
Local
Complexity
High
Privileges
None
User interaction
None
Confidentiality
None
Integrity
Low
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.1% · higher than 1% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
MT
Mbed TLS · trustedfirmware
3.2.0 before 3.6.7; 4.0.0 before 4.1.1 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-73064
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-73064
github.com
https://github.com/Mbed-TLS/mbedtls
mbed-tls.readthedocs.io
https://mbed-tls.readthedocs.io/en/latest/security-advisories/mbedtls-security-advisory-2026-07-random-generator-fault-tls-integrity/
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