CVE-2021-28235

Authentication vulnerability found in Etcd-io v.3.4.10 allows remote attackers to escalate privileges via the debug function.

Published: 2023-04-04 Last update: 2026-06-16 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2021-28235 is rated High Risk (65.9/100): CVSS Critical severity, with medium exploitation likelihood (EPSS 1.60%). EPSS rose +1.27% over the last day, indicating growing attacker interest. High exploitation likelihood—assess exposure and prioritize remediation.

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-2021-28235

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 0.34% 1.60% +1.27%
2 2026-04-27 0.38% 0.34% -0.05%
3 2026-04-04 — 0.38% —

Full EPSS history (17 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2021-28235

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
9.8 3.1 CRITICAL
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H 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:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 3.9 5.9 [email protected]

Weakness enumeration for CVE-2021-28235

GitHub Security Advisory for CVE-2021-28235

GHSA-gmph-wf7j-9gcm · Severity: critical · Ecosystem: go — Etcd-io Improper Authentication vulnerability

OS Trackers for CVE-2021-28235

vendor priority summary link
debian not yet assigned CVE-2021-28235 not yet assigned priority: Debian including 1 source packages (etcd), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 3, open 2. https://security-tracker.debian.org/tracker/CVE-2021-28235
redhat high — https://access.redhat.com/security/cve/CVE-2021-28235
suse high CVE-2021-28235 severity important: SUSE including 15 source package names (2.4.6-6.1:etcd-3.5.12-150000.7.6.1, etcd, …), 20 product×package rows across 7 product lines (Container containers/milvus, SUSE CaaS Platform 4.0, … (7 product lines)): Fixed 18, Known Not Affected 2. https://www.suse.com/security/cve/CVE-2021-28235/
ubuntu medium CVE-2021-28235 medium priority: Ubuntu including 1 source packages (etcd), 13 status rows across 13 suites (bionic, focal, jammy, kinetic, lunar, mantic, noble, oracular, plucky, questing, trusty, upstream, xenial): released 6, ignored 4, needs-triage 3. https://ubuntu.com/security/CVE-2021-28235

Affected software / configurations for CVE-2021-28235

Vendor Product Version Raw CPE
etcd etcd 3.4.10 cpe:2.3:a:etcd:etcd:3.4.10:*:*:*:*:*:*:*

References for CVE-2021-28235

cvelogic Threat Intelligence