CVE-2020-36478

Public Exploit

Description

An issue was discovered in Mbed TLS before 2.25.0 (and before 2.16.9 LTS and before 2.7.18 LTS). A NULL algorithm parameters entry looks identical to an array of REAL (size zero) and thus the certificate is considered valid. However, if the parameters do not match in any way, then the certificate should be considered invalid.

Category

7.5
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.25%
Third-Party Advisory siemens.com Third-Party Advisory github.com Third-Party Advisory github.com Third-Party Advisory github.com Third-Party Advisory github.com Third-Party Advisory debian.org Third-Party Advisory debian.org
Affected: n/a n/a
Published at:
Updated at:

References

Link Tags
https://github.com/ARMmbed/mbedtls/releases/tag/v2.25.0 third party advisory release notes
https://github.com/ARMmbed/mbedtls/releases/tag/v2.16.9 third party advisory release notes
https://github.com/ARMmbed/mbedtls/releases/tag/v2.7.18 third party advisory release notes
https://github.com/ARMmbed/mbedtls/issues/3629 third party advisory exploit
https://cert-portal.siemens.com/productcert/pdf/ssa-756638.pdf third party advisory patch
https://lists.debian.org/debian-lts-announce/2021/11/msg00021.html third party advisory mailing list
https://lists.debian.org/debian-lts-announce/2022/12/msg00036.html third party advisory mailing list

Frequently Asked Questions

What is the severity of CVE-2020-36478?
CVE-2020-36478 has been scored as a high severity vulnerability.
How to fix CVE-2020-36478?
To fix CVE-2020-36478, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2020-36478 being actively exploited in the wild?
It is possible that CVE-2020-36478 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
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