Summaryinfo

A vulnerability identified as critical has been detected in mbed TLS up to 3.6.5. Impacted is the function x509_inet_pton_ipv6. The manipulation leads to buffer overflow. This vulnerability is referenced as CVE-2026-25833. Remote exploitation of the attack is possible. No exploit is available. You should upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as critical, has been found in mbed TLS up to 3.6.5. This issue affects the function x509_inet_pton_ipv6. The manipulation with an unknown input leads to a buffer overflow vulnerability. Using CWE to declare the problem leads to CWE-120. The product copies an input buffer to an output buffer without verifying that the size of the input buffer is less than the size of the output buffer, leading to a buffer overflow. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

Mbed TLS 3.5.0 to 3.6.5 fixed in 3.6.6 and 4.1.0 has a buffer overflow in the x509_inet_pton_ipv6() function

It is possible to read the advisory at mbed-tls.readthedocs.io. The identification of this vulnerability is CVE-2026-25833 since 02/06/2026. The exploitation is known to be easy. The attack may be initiated remotely. Technical details of the vulnerability are known, but there is no available exploit.

Upgrading to version 3.6.6 or 4.1.0 eliminates this vulnerability.

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Productinfo

Name

• mbed TLS

Version

• 3.6.0
• 3.6.1
• 3.6.2
• 3.6.3
• 3.6.4
• 3.6.5

CPE 2.3info

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CPE 2.2info

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