Predictive Vulnerability Intelligence.

Product

  • Product
  • Pricing
  • Documentation

Company

  • About
  • Partnerships
  • Blog
  • Support

Legal

  • Terms
  • Privacy
  • Data Licensing

© 2026 FAUCET Technologies LLC. All rights reserved.

CVE-2021-3563

21
FAUCET Score

CVE-2021-3563 is a flaw in OpenStack Keystone that allows attackers to bypass password complexity requirements by only verifying the first 72 characters of an application secret. This vulnerability primarily impacts data confidentiality and integrity across various Debian and Red Hat OpenStack Keystone products. With a CVSS score of 7.4 (High), it presents a significant risk due to its network-based attack vector and high impact on confidentiality and integrity, despite requiring high attack complexity. Currently, there is no evidence of active exploitation, publicly available exploit code, or significant community discussion or media coverage.

Impacted Technologies

VendorProductVersion(s)CPE
All Versions ImpactedCPE matchmatch criteria
cpe:2.3:a:openstack:keystone:*:*:*:*:*:*:*:*
10.0CPE matchmatch criteria
cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*
11.0CPE matchmatch criteria
cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:*
10.0CPE matchmatch criteria
cpe:2.3:a:redhat:openstack_platform:10.0:*:*:*:*:*:*:*
13.0CPE matchmatch criteria
cpe:2.3:a:redhat:openstack_platform:13.0:*:*:*:*:*:*:*

CVSS Data

CVSS version used by this source: 3.1

7.4HIGH

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

Attack Vector
NETWORK
Attack Complexity
HIGH
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
HIGH
Integrity Impact
HIGH
Availability Impact
NONE
Exploitability Score
2.2
Impact Score
5.2
CvssVersion
3.1

Exploit Intelligence

EPSS Score
1.32%
Probability of exploitation in next 30 days
EPSS Percentile
67.9%
Percentile rank of EPSS score among Peer Group
As of 2026-07-27
Model: v2026.06.15
This CVE's current EPSS score of 0.0132 is in the 28th percentile among its peer group of 8,920 CVEs.

Social Chatter

The average CVE in this peer group has 0.0 Twitter, 0.1 Reddit, 0.1 Bluesky, 0.1 Mastodon, and 0.2 GitHub mentions.

Media Mentions

No media coverage found for this CVE.

The average CVE in this peer group has 0.1 InfoSec Media, 0.0 Vendor Blog, and 0.0 Security Researcher mentions.

Remediation

Vendor Patches (3)

redhatvendor investigatingvia nvd_reference
View patch
redhatno patchvia redhat_api
Product: Red Hat OpenStack Platform 16.1Fixed in: openstack-keystone
redhatend of lifevia redhat_api
Product: Red Hat OpenStack Platform 16.2Fixed in: openstack-keystone

Vendor Advisories (2)

pipGHSA-cc99-whm5-mmq3critical

Openstack Keystone Incorrect Authorization vulnerability

Aug 27, 2022
redhatCVE-2021-3563Moderate

Keystone: Verification of application credentials is silently length-limited

Feb 17, 2021

References

access.redhat.com / security/cve/CVE-2021-3563
Issue TrackingThird Party Advisory
bugs.launchpad.net / ossa/+bug/1901891
ExploitIssue TrackingThird Party AdvisoryVDB Entry
bugzilla.redhat.com / show_bug.cgi
ExploitIssue TrackingThird Party AdvisoryVendor Advisory
lists.debian.org / debian-lts-announce/2024/01/msg00007.html
security-tracker.debian.org / tracker/CVE-2021-3563
ExploitIssue TrackingThird Party Advisory