CVE-2021-28235
CWE-287Published: April 4, 2023· Updated: Jul 9, 2026
Official Description
Authentication vulnerability found in Etcd-io v.3.4.10 allows remote attackers to escalate privileges via the debug function.
Risk Analysis
This vulnerability in Etcd-io allows remote attackers to escalate privileges by abusing the debug function. With a CVSS score of 9.8, it represents a critical risk to system integrity and security. No active exploitation has been reported.
There is no known public exploit for this vulnerability, and it is not listed in CISA KEV. It is remotely exploitable due to the network attack vector.
Users should upgrade to a version of etcd that addresses this authentication flaw.
Technical Analysis
CVE-2021-28235 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.
The vulnerability requires no privileges and no user interaction, making it a prime target for automated exploitation campaigns and worm-like propagation.
A successful exploit results in complete confidentiality breach (data exposure), full integrity compromise (data manipulation), availability disruption (denial of service), with a CVSS base score of 9.8.
From a weakness classification perspective (CWE-287): Authentication bypass vulnerabilities allow attackers to access protected resources without valid credentials.
CVSS v3.1 Vector Breakdown
Affected Vendors & Products
Exploit & PoC Resources
All References (8)
Quick Facts
Related CVEs (CWE-287)
Recommended Actions
- →Apply vendor patches immediately
- →Monitor CVE-2021-28235 in threat intel feeds
- →Review IDS/IPS signatures for exploitation attempts