7.7

CVE-2026-40683: openstack keystone

Awaiting analysis
AliasesGHSA-pfx2-9x9m-7ghxPYSEC-2026-2550UBUNTU-CVE-2026-40683
Published 14-04-2026Last modified 05-08-2026

Vulnerability summary

CVE-2026-40683 is a high (CVSS 7.7) vulnerability in openstack keystone. EPSS estimates a 0.34% chance of exploitation in the next 30 days, higher than 27.1% of scored vulnerabilities.

Priority
Routine

Not severe (CVSS 7.7, network access); no exploitation reported by the 5 checked sources

Source freshness unavailable

How is this decided?
CVSS score
7.7/10
010
High · v3.1 (CVE.org)
EPSS score
0.34%
0%100%
Low · -0.04 pp in 30 days
KEVNot listedNot listed by any tracked catalog.
RansomwareNot flaggedNo ransomware use recorded.
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 1 · Related 2
RHSA-2026:39808CGA-4JRJ-75PC-RFHMUSN-8433-1

Timeline

  1. 14-04-2026
    PublishedVulnerability first disclosed.
  2. 05-08-2026
    Last modifiedVulnerability information updated.

Description

In OpenStack Keystone before 28.0.1, the LDAP identity backend does not convert the user enabled attribute to a boolean when the user_enabled_invert configuration option is False (the default). The _ldap_res_to_model method in the UserApi class only performed string-to-boolean conversion when user_enabled_invert was True. When False, the raw string value from LDAP (e.g., "FALSE") was used directly. Since non-empty strings are truthy in Python, users marked as disabled in LDAP were treated as enabled by Keystone, allowing them to authenticate and perform actions. All deployments using the LDAP identity backend without user_enabled_invert=True or user_enabled_emulation are affected.

CVSS metrics

6 scores · 6 sources · 1 version

EPSS trend

Probability

0.34%

Chance of exploitation in the next 30 days

Percentile

27%

Versus all other CVEs

30-day change

Decrease -0.04 pp

From 0.37% on 04-10-2026

04-10-202603-11-2026

Known exploited

Compare KEV catalogs
CISA KEV

Not in the CISA KEV catalog.

ENISA CNW

Not in the ENISA CNW catalog.

CIRCL

Not in the CIRCL catalog.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Version check

Known conditions: network-reachable, low-privilege account, no user interaction (CVSS vector). Other conditions: not stated in public data.

Chainguard2 products
  • openstack-keystone-2025.1All versions (No fix recorded)
  • openstack-keystone-2025.1-fipsAll versions (No fix recorded)
Debian1 product
  • keystone< 2:22.0.2-0+deb12u2 | < 2:27.0.0-3+deb13u3 | < 2:29.0.0~rc1-2
Openstack1 product
  • keystone≥ 8.0.0, < 25.0.1 | ≥ 26.0.0, < 26.1.1 | ≥ 27.0.0, < 27.0.1 | ≥ 28.0.0, < 28.0.1
PyPI1 product
  • keystone< 28.0.1
Ubuntu1 product
  • keystoneAll versions (No fix recorded) | < 2:21.0.1-0ubuntu2.4 | < 2:25.0.0-0ubuntu1.4 | < 2:28.0.0-0ubuntu1.3

5 vendors · 6 products

References

13 links
Show all 13 references