High severity · published Aug 23, 2021
CVE-2020-36475
An issue was discovered in Mbed TLS before 2.25.0 (and before 2.16.9 LTS and before 2.7.18 LTS)
7.5
CVSS
1.9%
EPSS
No
On KEV
Description
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)1.9% · higher than 80% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
DL
Debian Linux · Debian
9.0; 10.0 · source: NVD
LC
Logo! Cmr2020 Firmware · Siemens
before 2.2 · source: NVD
LC
Logo! Cmr2040 Firmware · Siemens
before 2.2 · source: NVD
MT
Mbed Tls · Arm
before 2.7.18; 2.8.0 before 2.16.9; 2.17.0 before 2.25.0 · source: NVD
SR
Simatic Rtu3000c Firmware · Siemens
All versions, or not specified · source: NVD
SR
Simatic Rtu3030c Firmware · Siemens
All versions, or not specified · source: NVD
SR
Simatic Rtu3031c Firmware · Siemens
All versions, or not specified · source: NVD
SR
Simatic Rtu3041c Firmware · Siemens
All versions, or not specified · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2020-36475
CVE.org
https://www.cve.org/CVERecord?id=CVE-2020-36475
Patch
https://cert-portal.siemens.com/productcert/pdf/ssa-756638.pdf
Release Notes
https://github.com/ARMmbed/mbedtls/releases/tag/v2.16.9
Release Notes
https://github.com/ARMmbed/mbedtls/releases/tag/v2.25.0
Release Notes
https://github.com/ARMmbed/mbedtls/releases/tag/v2.7.18
Mailing List
https://lists.debian.org/debian-lts-announce/2021/11/msg00021.html
Mailing List
https://lists.debian.org/debian-lts-announce/2022/12/msg00036.html
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