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Vulnerability record · public intelligence
CVE-2021-20288
UNKNOWN

CVE-2021-20288

Published Apr 15, 2021 · Updated Nov 3, 2026

Severity · CVSSUNKNOWN · Not scored
Known exploitationNot listed
EPSS / likelihood2.13%
QFinch risk scoreNot available

Original summary

Normalized public record · Updated Nov 3, 2026

An authentication flaw was found in ceph in versions before 14.2.20. When the monitor handles CEPHX_GET_AUTH_SESSION_KEY requests, it doesn't sanitize other_keys, allowing key reuse. An attacker who can request a global_id can exploit the ability of any user to request a global_id previously associated with another user, as ceph does not force the reuse of old keys to generate new ones. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.

Publisher and source text is retained separately from QFinch interpretation.

QFinch assessment

An authentication flaw was found in ceph in versions before 14.2.20. When the monitor handles CEPHX_GET_AUTH_SESSION_KEY requests, it doesn't sanitize other_keys, allowing key reuse. An attacker who can request a global_id can exploit the ability of any user to request a global_id previously associated with another user, as ceph does not force the reuse of old keys to generate new ones. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.

Evidence: public source records

Affected products

Affected scope reported by the available public evidence
Affected package, product or rangeFix status
Consult the referenced vendor advisory for affected versions.Consult source advisory

Matching a version is only one part of assessing exposure. QFinch has not assessed your environment on this public page.

Remediation

Apply the vendor-supported fixed release or mitigation, then verify the affected component is no longer reachable.

  1. Confirm the affected product and reachable code path exist in your environment.
  2. Apply the vendor-supported patch or mitigation from the primary advisory.
  3. Rescan the exact deployed revision and retain verification evidence.
Review primary references

Evidence coverage

FIRST-EPSSCVE-LIST-V5
SSVC priority
MEDIUM
Confidence
Not available
Aliases
None reported

Scores appear only when corresponding evidence exists. Missing data is never interpreted as zero risk.

Sources and record history

  1. bugzilla.redhat.com ↗
  2. FEDORA-2021-e29c1ee892 ↗
  3. FEDORA-2021-e65b9fb52e ↗
  4. FEDORA-2021-168fbed46f ↗
  5. GLSA-202105-39 ↗
  6. [debian-lts-announce] 20231023 [SECURITY] [DLA 3629-1] ceph security update ↗

Record history

Published Apr 15, 2021 · Last refreshed Nov 3, 2026

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