7.5
HIGH
CVE-2020-36475
Mbed TLS Denial of Service Vulnerability
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.

INFO

Published Date :

Aug. 23, 2021, 2:15 a.m.

Last Modified :

Nov. 21, 2024, 5:29 a.m.

Remotely Exploitable :

Yes !

Impact Score :

3.6

Exploitability Score :

3.9
Affected Products

The following products are affected by CVE-2020-36475 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Siemens logo\!_cmr2020_firmware
2 Siemens logo\!_cmr2040_firmware
3 Siemens simatic_rtu3030c_firmware
4 Siemens simatic_rtu3031c_firmware
5 Siemens simatic_rtu3041c_firmware
6 Siemens simatic_rtu3000c_firmware
7 Siemens logo\!_cmr2040
8 Siemens logo\!_cmr2020
9 Siemens simatic_rtu3030c
10 Siemens simatic_rtu3031c
11 Siemens simatic_rtu3041c
12 Siemens simatic_rtu3000c
1 Debian debian_linux
1 Arm mbed_tls
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2020-36475.

URL Resource
https://cert-portal.siemens.com/productcert/pdf/ssa-756638.pdf Patch Third Party Advisory
https://github.com/ARMmbed/mbedtls/releases/tag/v2.16.9 Release Notes Third Party Advisory
https://github.com/ARMmbed/mbedtls/releases/tag/v2.25.0 Release Notes Third Party Advisory
https://github.com/ARMmbed/mbedtls/releases/tag/v2.7.18 Release Notes Third Party Advisory
https://lists.debian.org/debian-lts-announce/2021/11/msg00021.html Mailing List Third Party Advisory
https://lists.debian.org/debian-lts-announce/2022/12/msg00036.html Mailing List Third Party Advisory
https://cert-portal.siemens.com/productcert/pdf/ssa-756638.pdf Patch Third Party Advisory
https://github.com/ARMmbed/mbedtls/releases/tag/v2.16.9 Release Notes Third Party Advisory
https://github.com/ARMmbed/mbedtls/releases/tag/v2.25.0 Release Notes Third Party Advisory
https://github.com/ARMmbed/mbedtls/releases/tag/v2.7.18 Release Notes Third Party Advisory
https://lists.debian.org/debian-lts-announce/2021/11/msg00021.html Mailing List Third Party Advisory
https://lists.debian.org/debian-lts-announce/2022/12/msg00036.html Mailing List Third Party Advisory

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2020-36475 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2020-36475 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • CVE Modified by af854a3a-2127-422b-91ae-364da2661108

    Nov. 21, 2024

    Action Type Old Value New Value
    Added Reference https://cert-portal.siemens.com/productcert/pdf/ssa-756638.pdf
    Added Reference https://github.com/ARMmbed/mbedtls/releases/tag/v2.16.9
    Added Reference https://github.com/ARMmbed/mbedtls/releases/tag/v2.25.0
    Added Reference https://github.com/ARMmbed/mbedtls/releases/tag/v2.7.18
    Added Reference https://lists.debian.org/debian-lts-announce/2021/11/msg00021.html
    Added Reference https://lists.debian.org/debian-lts-announce/2022/12/msg00036.html
  • CVE Modified by [email protected]

    May. 14, 2024

    Action Type Old Value New Value
  • Modified Analysis by [email protected]

    Jan. 11, 2023

    Action Type Old Value New Value
    Changed Reference Type https://lists.debian.org/debian-lts-announce/2022/12/msg00036.html No Types Assigned https://lists.debian.org/debian-lts-announce/2022/12/msg00036.html Mailing List, Third Party Advisory
    Changed CPE Configuration OR *cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:* OR *cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:* *cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*
  • CVE Modified by [email protected]

    Dec. 26, 2022

    Action Type Old Value New Value
    Added Reference https://lists.debian.org/debian-lts-announce/2022/12/msg00036.html [No Types Assigned]
  • Modified Analysis by [email protected]

    Nov. 26, 2021

    Action Type Old Value New Value
    Changed Reference Type https://lists.debian.org/debian-lts-announce/2021/11/msg00021.html No Types Assigned https://lists.debian.org/debian-lts-announce/2021/11/msg00021.html Mailing List, Third Party Advisory
    Added CPE Configuration OR *cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*
  • CVE Modified by [email protected]

    Nov. 23, 2021

    Action Type Old Value New Value
    Added Reference https://lists.debian.org/debian-lts-announce/2021/11/msg00021.html [No Types Assigned]
  • Modified Analysis by [email protected]

    Sep. 16, 2021

    Action Type Old Value New Value
    Changed Reference Type https://cert-portal.siemens.com/productcert/pdf/ssa-756638.pdf No Types Assigned https://cert-portal.siemens.com/productcert/pdf/ssa-756638.pdf Patch, Third Party Advisory
    Added CPE Configuration AND OR *cpe:2.3:o:siemens:logo\!_cmr2020_firmware:*:*:*:*:*:*:*:* versions up to (excluding) 2.2 OR cpe:2.3:h:siemens:logo\!_cmr2020:-:*:*:*:*:*:*:*
    Added CPE Configuration AND OR *cpe:2.3:o:siemens:logo\!_cmr2040_firmware:*:*:*:*:*:*:*:* versions up to (excluding) 2.2 OR cpe:2.3:h:siemens:logo\!_cmr2040:-:*:*:*:*:*:*:*
    Added CPE Configuration AND OR *cpe:2.3:o:siemens:simatic_rtu3031c_firmware:*:*:*:*:*:*:*:* OR cpe:2.3:h:siemens:simatic_rtu3031c:-:*:*:*:*:*:*:*
    Added CPE Configuration AND OR *cpe:2.3:o:siemens:simatic_rtu3041c_firmware:*:*:*:*:*:*:*:* OR cpe:2.3:h:siemens:simatic_rtu3041c:-:*:*:*:*:*:*:*
    Added CPE Configuration AND OR *cpe:2.3:o:siemens:simatic_rtu3030c_firmware:*:*:*:*:*:*:*:* OR cpe:2.3:h:siemens:simatic_rtu3030c:-:*:*:*:*:*:*:*
    Added CPE Configuration AND OR *cpe:2.3:o:siemens:simatic_rtu3000c_firmware:*:*:*:*:*:*:*:* OR cpe:2.3:h:siemens:simatic_rtu3000c:-:*:*:*:*:*:*:*
  • CVE Modified by [email protected]

    Sep. 14, 2021

    Action Type Old Value New Value
    Added Reference https://cert-portal.siemens.com/productcert/pdf/ssa-756638.pdf [No Types Assigned]
  • Initial Analysis by [email protected]

    Aug. 26, 2021

    Action Type Old Value New Value
    Added CVSS V2 NIST (AV:N/AC:L/Au:N/C:N/I:N/A:P)
    Added CVSS V3.1 NIST AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
    Changed Reference Type https://github.com/ARMmbed/mbedtls/releases/tag/v2.16.9 No Types Assigned https://github.com/ARMmbed/mbedtls/releases/tag/v2.16.9 Release Notes, Third Party Advisory
    Changed Reference Type https://github.com/ARMmbed/mbedtls/releases/tag/v2.25.0 No Types Assigned https://github.com/ARMmbed/mbedtls/releases/tag/v2.25.0 Release Notes, Third Party Advisory
    Changed Reference Type https://github.com/ARMmbed/mbedtls/releases/tag/v2.7.18 No Types Assigned https://github.com/ARMmbed/mbedtls/releases/tag/v2.7.18 Release Notes, Third Party Advisory
    Added CWE NIST CWE-131
    Added CPE Configuration OR *cpe:2.3:a:arm:mbed_tls:*:*:*:*:*:*:*:* versions up to (excluding) 2.7.18 *cpe:2.3:a:arm:mbed_tls:*:*:*:*:*:*:*:* versions from (including) 2.8.0 up to (excluding) 2.16.9 *cpe:2.3:a:arm:mbed_tls:*:*:*:*:*:*:*:* versions from (including) 2.17.0 up to (excluding) 2.25.0
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2020-36475 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2020-36475 weaknesses.

Exploit Prediction

EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days.

0.66 }} -0.41%

score

0.79548

percentile

CVSS31 - Vulnerability Scoring System
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