What is CVE-2021-37588?

CVE-2021-37588 is a medium-severity vulnerability in Jhu Charm, classified under Use of a Broken or Risky Cryptographic Algorithm. CVSS score: 5.9/10. Published 2021-07-30.

How severe is CVE-2021-37588?

Medium severity. CVSS v3 base score is 5.9 out of 10.

Vulnerability in Jhu Charm

CVE-2021-37588

In Charm 0.43, any two users can collude to achieve the ability to decrypt YCT14 data.

Vulnerability class: POODLE (CVE-2014-3566)

Published 2021-07-30 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 5.9 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N.

EPSS exploit prediction

EPSS: 0.009 (58.4th percentile), scored 2026-09-30.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 58th percentile — 58.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.009 · newest: 0.009 · change: 0.000

Affected products

Jhu Charm — versions 0.43

Weakness classification (CWE)

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

References

github.com/JHUISI/charm/issues/276 (Third Party Advisory, Issue Tracking)
eprint.iacr.org/2020/460 (Third Party Advisory)
www2.hci.uni-hannover.de/papers/Tan2019.pdf (Technical Description, Third Party Advisory)
github.com/JHUISI/charm/blob/dev/charm/schemes/abenc/abenc_yct14.py (Third Party Advisory)

Frequently asked questions

What is CVE-2021-37588?: CVE-2021-37588 is a medium-severity vulnerability in Jhu Charm, classified under Use of a Broken or Risky Cryptographic Algorithm. CVSS score: 5.9/10. Published 2021-07-30.
How severe is CVE-2021-37588?: Medium severity. CVSS v3 base score is 5.9 out of 10.