CVE-2021-3979

A key length flaw was found in Red Hat Ceph Storage. An attacker can exploit the fact that the key length is incorrectly passed in an encryption algorithm to create a non random key, which is weaker and can be exploited for loss of confidentiality and integrity on encrypted disks.

Published: 2022-08-25 Last update: 2025-11-03 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2021-3979 is rated Low Risk (37.8/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.42%). Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2021-3979

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.27% 0.42% +0.14%
2 2026-02-22 0.23% 0.27% +0.05%
3 2026-02-21 — 0.23% —

Full EPSS history (21 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2021-3979

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
6.5 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:N)
Service keeps running; no real outage angle.
 3.9 2.5 [email protected]

Weakness enumeration for CVE-2021-3979

OS Trackers for CVE-2021-3979

vendor priority summary link
debian not yet assigned CVE-2021-3979 not yet assigned priority: Debian including 1 source packages (ceph), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2021-3979
redhat medium — https://access.redhat.com/security/cve/CVE-2021-3979
suse medium — https://www.suse.com/security/cve/CVE-2021-3979/
ubuntu low CVE-2021-3979 low priority: Ubuntu including 1 source packages (ceph), 14 status rows across 14 suites (bionic, focal, hirsute, impish, jammy, kinetic, lunar, mantic, noble, oracular, plucky, trusty, upstream, xenial): not-affected 9, released 3, ignored 2. https://ubuntu.com/security/CVE-2021-3979

Affected software / configurations for CVE-2021-3979

Vendor Product Version Raw CPE
redhat ceph_storage 3.0 cpe:2.3:a:redhat:ceph_storage:3.0:*:*:*:*:*:*:*
redhat ceph_storage 4.3 cpe:2.3:a:redhat:ceph_storage:4.3:*:*:*:*:*:*:*
redhat ceph_storage 5.1 cpe:2.3:a:redhat:ceph_storage:5.1:*:*:*:*:*:*:*
redhat openshift_container_storage 4.0 cpe:2.3:a:redhat:openshift_container_storage:4.0:*:*:*:*:*:*:*
redhat openshift_data_foundation 4.0 cpe:2.3:a:redhat:openshift_data_foundation:4.0:*:*:*:*:*:*:*
redhat openstack_platform 13.0 cpe:2.3:a:redhat:openstack_platform:13.0:*:*:*:*:*:*:*
redhat ceph_storage_for_ibm_z_systems 4.0 cpe:2.3:o:redhat:ceph_storage_for_ibm_z_systems:4.0:*:*:*:*:*:*:*
redhat ceph_storage 4.0 cpe:2.3:a:redhat:ceph_storage:4.0:*:*:*:*:*:*:*
redhat ceph_storage 5.0 cpe:2.3:a:redhat:ceph_storage:5.0:*:*:*:*:*:*:*
redhat ceph_storage_for_power 4.0 cpe:2.3:a:redhat:ceph_storage_for_power:4.0:*:*:*:*:*:*:*
fedoraproject fedora 35 cpe:2.3:o:fedoraproject:fedora:35:*:*:*:*:*:*:*
fedoraproject fedora 37 cpe:2.3:o:fedoraproject:fedora:37:*:*:*:*:*:*:*

References for CVE-2021-3979

cvelogic Threat Intelligence