Vulnerabilities > CVE-2020-36475 - Incorrect Calculation of Buffer Size vulnerability in multiple products
Attack vector
NETWORK Attack complexity
LOW Privileges required
NONE Confidentiality impact
NONE Integrity impact
NONE Availability impact
HIGH Summary
An issue was discovered in Mbed TLS before 2.25.0 (and before 2.16.9 LTS and before 2.7.18 LTS). The calculations performed by mbedtls_mpi_exp_mod are not limited; thus, supplying overly large parameters could lead to denial of service when generating Diffie-Hellman key pairs.
Vulnerable Configurations
Common Weakness Enumeration (CWE)
Common Attack Pattern Enumeration and Classification (CAPEC)
- Overflow Buffers Buffer Overflow attacks target improper or missing bounds checking on buffer operations, typically triggered by input injected by an attacker. As a consequence, an attacker is able to write past the boundaries of allocated buffer regions in memory, causing a program crash or potentially redirection of execution as per the attackers' choice.
- Buffer Overflow via Parameter Expansion In this attack, the target software is given input that the attacker knows will be modified and expanded in size during processing. This attack relies on the target software failing to anticipate that the expanded data may exceed some internal limit, thereby creating a buffer overflow.
References
- https://github.com/ARMmbed/mbedtls/releases/tag/v2.16.9
- https://github.com/ARMmbed/mbedtls/releases/tag/v2.25.0
- https://github.com/ARMmbed/mbedtls/releases/tag/v2.7.18
- https://cert-portal.siemens.com/productcert/pdf/ssa-756638.pdf
- https://lists.debian.org/debian-lts-announce/2021/11/msg00021.html
- https://lists.debian.org/debian-lts-announce/2022/12/msg00036.html