What is CVE-2020-36363?

CVE-2020-36363 is a critical-severity vulnerability in Amazon Cloudfront, classified under Use of a Broken or Risky Cryptographic Algorithm. CVSS score: 9.8/10. Published 2021-08-12.

How severe is CVE-2020-36363?

Critical severity. CVSS v3 base score is 9.8 out of 10.

Vulnerability in Amazon Cloudfront

CVE-2020-36363

Amazon AWS CloudFront TLSv1.2_2019 allows TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256 and TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384, which some entities consider to be weak ciphers.

Vulnerability class: POODLE (CVE-2014-3566)

Published 2021-08-12 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.007 (51.5th percentile), scored 2026-09-30.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 52nd percentile — 51.5% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.007 · newest: 0.007 · change: 0.000

Affected products

Amazon Cloudfront — versions 1.2_2019

Weakness classification (CWE)

CWE-327 — Use of a Broken or Risky Cryptographic Algorithm

References

stackoverflow.com/questions/62071604 (Third Party Advisory)
aws.amazon.com/about-aws/whats-new/2020/07/cloudfront-tls-security-policy/ (Vendor Advisory)

Frequently asked questions

What is CVE-2020-36363?: CVE-2020-36363 is a critical-severity vulnerability in Amazon Cloudfront, classified under Use of a Broken or Risky Cryptographic Algorithm. CVSS score: 9.8/10. Published 2021-08-12.
How severe is CVE-2020-36363?: Critical severity. CVSS v3 base score is 9.8 out of 10.