CVE-2025-47917

Publication date 20 July 2025

Last updated 23 July 2025


Ubuntu priority

Cvss 3 Severity Score

8.9 · High

Score breakdown

Description

Mbed TLS before 3.6.4 allows a use-after-free in certain situations of applications that are developed in accordance with the documentation. The function mbedtls_x509_string_to_names() takes a head argument that is documented as an output argument. The documentation does not suggest that the function will free that pointer; however, the function does call mbedtls_asn1_free_named_data_list() on that argument, which performs a deep free(). As a result, application code that uses this function (relying only on documented behavior) is likely to still hold pointers to the memory blocks that were freed, resulting in a high risk of use-after-free or double-free. In particular, the two sample programs x509/cert_write and x509/cert_req are affected (use-after-free if the san string contains more than one DN).

Status

Package Ubuntu Release Status
mbedtls 25.04 plucky
Needs evaluation
24.04 LTS noble
Needs evaluation
22.04 LTS jammy
Needs evaluation
20.04 LTS focal
Needs evaluation
18.04 LTS bionic
Needs evaluation
16.04 LTS xenial
Needs evaluation

Severity score breakdown

Parameter Value
Base score 8.9 · High
Attack vector Network
Attack complexity High
Privileges required None
User interaction None
Scope Changed
Confidentiality Low
Integrity impact High
Availability impact High
Vector CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:H/A:H