CVE-2021-3990

Name: CVE-2021-3990
Creator: NVD / NIST
Published: 2021-12-01T11:15:07.977+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 6.5/10EPSS 0.86%

Last modified Jun 17, 2026

CVE-2021-3990 is a medium-severity vulnerability rated 6.5/10 on the CVSS scale. showdoc is vulnerable to Use of Cryptographically Weak Pseudo-Random Number Generator (PRNG). EPSS estimates a 0.86% chance of exploitation in the next 30 days.

Description

showdoc is vulnerable to Use of Cryptographically Weak Pseudo-Random Number Generator (PRNG)

Metrics

CVSS 3.1

6.5/10

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N

EPSS Probability

0.86%

53.9th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-338

Affected Software

Vendor	Product	Versions
Showdoc	Showdoc	< 2.9.13

References

https://github.com/star7th/showdoc/commit/a9886f26c08225e0adca75c67dfca3f7c42b87d0Patch, Third Party Advisory
https://huntr.dev/bounties/0680067d-56a7-4412-b06e-a267e850ae9fExploit, Patch, Third Party Advisory
https://github.com/star7th/showdoc/commit/a9886f26c08225e0adca75c67dfca3f7c42b87d0Patch, Third Party Advisory
https://huntr.dev/bounties/0680067d-56a7-4412-b06e-a267e850ae9fExploit, Patch, Third Party Advisory

Timeline

Published: Dec 1, 2021
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-3990?

showdoc is vulnerable to Use of Cryptographically Weak Pseudo-Random Number Generator (PRNG)

How severe is CVE-2021-3990?

CVE-2021-3990 has a CVSS score of 6.5/10 (MEDIUM severity). The EPSS model estimates a 0.86% probability of exploitation in the next 30 days.

How do I fix CVE-2021-3990?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2021-3990?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST